From 41708ed8d33f43351da5036298943ae4468a4481 Mon Sep 17 00:00:00 2001
From: Matthew Walsh <matthew.walsh@consensys.net>
Date: Sun, 4 Jan 2026 21:17:23 +0000
Subject: [PATCH 01/13] Add isMaxAmount property

Add messenger action and method.
Update trade type and amount.
Update totals.
---
 .../src/TransactionPayController.ts               | 15 ++++++++++++++-
 packages/transaction-pay-controller/src/index.ts  |  1 +
 .../src/strategy/relay/relay-quotes.ts            | 11 +++++++++--
 .../src/strategy/relay/types.ts                   |  2 +-
 packages/transaction-pay-controller/src/types.ts  | 10 ++++++++++
 .../src/utils/source-amounts.ts                   | 13 ++++++++++++-
 .../src/utils/totals.ts                           |  9 +++++++++
 .../src/utils/transaction.ts                      | 12 ++++++++++++
 8 files changed, 68 insertions(+), 5 deletions(-)

diff --git a/packages/transaction-pay-controller/src/TransactionPayController.ts b/packages/transaction-pay-controller/src/TransactionPayController.ts
index e1602ba8abf..b4b240a61d9 100644
--- a/packages/transaction-pay-controller/src/TransactionPayController.ts
+++ b/packages/transaction-pay-controller/src/TransactionPayController.ts
@@ -81,6 +81,12 @@ export class TransactionPayController extends BaseController<
     });
   }
 
+  setIsMax(transactionId: string, isMaxAmount: boolean): void {
+    this.#updateTransactionData(transactionId, (transactionData) => {
+      transactionData.isMaxAmount = isMaxAmount;
+    });
+  }
+
   #removeTransactionData(transactionId: string): void {
     this.update((state) => {
       delete state.transactionData[transactionId];
@@ -98,6 +104,7 @@ export class TransactionPayController extends BaseController<
       let current = transactionData[transactionId];
       const originalPaymentToken = current?.paymentToken;
       const originalTokens = current?.tokens;
+      const originalIsMaxAmount = current?.isMaxAmount;
 
       if (!current) {
         transactionData[transactionId] = {
@@ -114,8 +121,9 @@ export class TransactionPayController extends BaseController<
         current.paymentToken !== originalPaymentToken;
 
       const isTokensUpdated = current.tokens !== originalTokens;
+      const isIsMaxUpdated = current.isMaxAmount !== originalIsMaxAmount;
 
-      if (isPaymentTokenUpdated || isTokensUpdated) {
+      if (isPaymentTokenUpdated || isTokensUpdated || isIsMaxUpdated) {
         updateSourceAmounts(transactionId, current as never, this.messenger);
 
         shouldUpdateQuotes = true;
@@ -148,5 +156,10 @@ export class TransactionPayController extends BaseController<
       'TransactionPayController:updatePaymentToken',
       this.updatePaymentToken.bind(this),
     );
+
+    this.messenger.registerActionHandler(
+      'TransactionPayController:setIsMax',
+      this.setIsMax.bind(this),
+    );
   }
 }
diff --git a/packages/transaction-pay-controller/src/index.ts b/packages/transaction-pay-controller/src/index.ts
index 04b8fe4d86b..380e35a42d2 100644
--- a/packages/transaction-pay-controller/src/index.ts
+++ b/packages/transaction-pay-controller/src/index.ts
@@ -6,6 +6,7 @@ export type {
   TransactionPayControllerGetStrategyAction,
   TransactionPayControllerMessenger,
   TransactionPayControllerOptions,
+  TransactionPayControllerSetIsMaxAction,
   TransactionPayControllerState,
   TransactionPayControllerStateChangeEvent,
   TransactionPayControllerUpdatePaymentTokenAction,
diff --git a/packages/transaction-pay-controller/src/strategy/relay/relay-quotes.ts b/packages/transaction-pay-controller/src/strategy/relay/relay-quotes.ts
index 3ddb0478788..1ddd9b3b612 100644
--- a/packages/transaction-pay-controller/src/strategy/relay/relay-quotes.ts
+++ b/packages/transaction-pay-controller/src/strategy/relay/relay-quotes.ts
@@ -89,16 +89,23 @@ async function getSingleQuote(
     0,
   );
 
+  const { transactionData } = messenger.call(
+    'TransactionPayController:getState',
+  );
+  const isMaxAmount = transactionData[transaction.id]?.isMaxAmount;
+
   try {
     const body: RelayQuoteRequest = {
-      amount: request.targetAmountMinimum,
+      amount: isMaxAmount
+        ? request.sourceTokenAmount
+        : request.targetAmountMinimum,
       destinationChainId: Number(request.targetChainId),
       destinationCurrency: request.targetTokenAddress,
       originChainId: Number(request.sourceChainId),
       originCurrency: request.sourceTokenAddress,
       recipient: request.from,
       slippageTolerance,
-      tradeType: 'EXPECTED_OUTPUT',
+      tradeType: isMaxAmount ? 'EXACT_INPUT' : 'EXPECTED_OUTPUT',
       user: request.from,
     };
 
diff --git a/packages/transaction-pay-controller/src/strategy/relay/types.ts b/packages/transaction-pay-controller/src/strategy/relay/types.ts
index fbab58bc223..2eb031ee260 100644
--- a/packages/transaction-pay-controller/src/strategy/relay/types.ts
+++ b/packages/transaction-pay-controller/src/strategy/relay/types.ts
@@ -17,7 +17,7 @@ export type RelayQuoteRequest = {
   recipient: Hex;
   refundTo?: Hex;
   slippageTolerance?: string;
-  tradeType: 'EXPECTED_OUTPUT' | 'EXACT_OUTPUT';
+  tradeType: 'EXPECTED_OUTPUT' | 'EXACT_OUTPUT' | 'EXACT_INPUT';
   txs?: {
     to: Hex;
     data: Hex;
diff --git a/packages/transaction-pay-controller/src/types.ts b/packages/transaction-pay-controller/src/types.ts
index 1a2595f6d3a..8120ba307b7 100644
--- a/packages/transaction-pay-controller/src/types.ts
+++ b/packages/transaction-pay-controller/src/types.ts
@@ -85,6 +85,12 @@ export type TransactionPayControllerUpdatePaymentTokenAction = {
   handler: (request: UpdatePaymentTokenRequest) => void;
 };
 
+/** Action to set the max amount flag for a transaction. */
+export type TransactionPayControllerSetIsMaxAction = {
+  type: `${typeof CONTROLLER_NAME}:setIsMax`;
+  handler: (transactionId: string, isMaxAmount: boolean) => void;
+};
+
 export type TransactionPayControllerStateChangeEvent =
   ControllerStateChangeEvent<
     typeof CONTROLLER_NAME,
@@ -95,6 +101,7 @@ export type TransactionPayControllerActions =
   | TransactionPayControllerGetDelegationTransactionAction
   | TransactionPayControllerGetStateAction
   | TransactionPayControllerGetStrategyAction
+  | TransactionPayControllerSetIsMaxAction
   | TransactionPayControllerUpdatePaymentTokenAction;
 
 export type TransactionPayControllerEvents =
@@ -132,6 +139,9 @@ export type TransactionData = {
   /** Whether quotes are currently being retrieved. */
   isLoading: boolean;
 
+  /** Whether the user has selected the maximum amount. */
+  isMaxAmount?: boolean;
+
   /** Source token selected for the transaction. */
   paymentToken?: TransactionPaymentToken;
 
diff --git a/packages/transaction-pay-controller/src/utils/source-amounts.ts b/packages/transaction-pay-controller/src/utils/source-amounts.ts
index 2677c4861bb..339b476f523 100644
--- a/packages/transaction-pay-controller/src/utils/source-amounts.ts
+++ b/packages/transaction-pay-controller/src/utils/source-amounts.ts
@@ -2,7 +2,7 @@ import { createModuleLogger } from '@metamask/utils';
 import { BigNumber } from 'bignumber.js';
 
 import { getTokenFiatRate } from './token';
-import { getTransaction } from './transaction';
+import { getTransaction, getTransactionData } from './transaction';
 import type {
   TransactionPayControllerMessenger,
   TransactionPaymentToken,
@@ -119,6 +119,17 @@ function calculateSourceAmount(
     return undefined;
   }
 
+  const transactionData = getTransactionData(transactionId, messenger);
+  const isMaxAmount = transactionData?.isMaxAmount ?? false;
+
+  if (isMaxAmount) {
+    return {
+      sourceAmountHuman: paymentToken.balanceHuman,
+      sourceAmountRaw: paymentToken.balanceRaw,
+      targetTokenAddress: token.address,
+    };
+  }
+
   return {
     sourceAmountHuman,
     sourceAmountRaw,
diff --git a/packages/transaction-pay-controller/src/utils/totals.ts b/packages/transaction-pay-controller/src/utils/totals.ts
index d3ece1efaae..9efcf38ece6 100644
--- a/packages/transaction-pay-controller/src/utils/totals.ts
+++ b/packages/transaction-pay-controller/src/utils/totals.ts
@@ -2,6 +2,7 @@ import type { TransactionMeta } from '@metamask/transaction-controller';
 import { BigNumber } from 'bignumber.js';
 
 import { calculateTransactionGasCost } from './gas';
+import { getTransactionData } from './transaction';
 import type {
   Amount,
   FiatValue,
@@ -60,6 +61,8 @@ export function calculateTotals({
     (singleToken) => !singleToken.skipIfBalance,
   );
 
+  const transactionData = getTransactionData(transaction.id, messenger);
+  const isMaxAmount = transactionData?.isMaxAmount ?? false;
   const amountFiat = sumProperty(quoteTokens, (token) => token.amountFiat);
   const amountUsd = sumProperty(quoteTokens, (token) => token.amountUsd);
 
@@ -67,12 +70,18 @@ export function calculateTotals({
     .plus(sourceNetworkFeeEstimate.fiat)
     .plus(targetNetworkFee.fiat)
     .plus(amountFiat)
+    .plus(isMaxAmount ? sourceAmount.fiat : 0)
+    .minus(isMaxAmount ? amountFiat : 0)
+    .minus(isMaxAmount ? providerFee.fiat : 0)
     .toString(10);
 
   const totalUsd = new BigNumber(providerFee.usd)
     .plus(sourceNetworkFeeEstimate.usd)
     .plus(targetNetworkFee.usd)
     .plus(amountUsd)
+    .plus(isMaxAmount ? sourceAmount.usd : 0)
+    .minus(isMaxAmount ? amountUsd : 0)
+    .minus(isMaxAmount ? providerFee.usd : 0)
     .toString(10);
 
   const estimatedDuration = Number(
diff --git a/packages/transaction-pay-controller/src/utils/transaction.ts b/packages/transaction-pay-controller/src/utils/transaction.ts
index 7a5d14d2285..4b834be3f1d 100644
--- a/packages/transaction-pay-controller/src/utils/transaction.ts
+++ b/packages/transaction-pay-controller/src/utils/transaction.ts
@@ -7,6 +7,7 @@ import { cloneDeep } from 'lodash';
 import { parseRequiredTokens } from './required-tokens';
 import { projectLogger } from '../logger';
 import type {
+  TransactionData,
   TransactionPayControllerMessenger,
   UpdateTransactionDataCallback,
 } from '../types';
@@ -39,6 +40,17 @@ export function getTransaction(
   );
 }
 
+export function getTransactionData(
+  transactionId: string,
+  messenger: TransactionPayControllerMessenger,
+): TransactionData | undefined {
+  const { transactionData } = messenger.call(
+    'TransactionPayController:getState',
+  );
+
+  return transactionData[transactionId];
+}
+
 /**
  * Poll for transaction changes and update the transaction data accordingly.
  *

From 84b739eabb02d84de37e3ea979404f86beca9222 Mon Sep 17 00:00:00 2001
From: Matthew Walsh <matthew.walsh@consensys.net>
Date: Sun, 4 Jan 2026 21:31:44 +0000
Subject: [PATCH 02/13] Add transaction util unit tests

---
 .../src/utils/transaction.test.ts             | 31 ++++++++++++++++++-
 .../src/utils/transaction.ts                  |  7 +++++
 2 files changed, 37 insertions(+), 1 deletion(-)

diff --git a/packages/transaction-pay-controller/src/utils/transaction.test.ts b/packages/transaction-pay-controller/src/utils/transaction.test.ts
index bd6f7ddb6ee..48716943906 100644
--- a/packages/transaction-pay-controller/src/utils/transaction.test.ts
+++ b/packages/transaction-pay-controller/src/utils/transaction.test.ts
@@ -12,6 +12,7 @@ import {
   FINALIZED_STATUSES,
   collectTransactionIds,
   getTransaction,
+  getTransactionData,
   pollTransactionChanges,
   updateTransaction,
   waitForTransactionConfirmed,
@@ -41,11 +42,17 @@ const TRANSCTION_TOKEN_REQUIRED_MOCK = {
   balanceUsd: '5',
 } as TransactionPayRequiredToken;
 
+const TRANSACTION_DATA_MOCK = {
+  isLoading: false,
+  tokens: [TRANSCTION_TOKEN_REQUIRED_MOCK],
+} as TransactionData;
+
 describe('Transaction Utils', () => {
   const parseRequiredTokensMock = jest.mocked(parseRequiredTokens);
   const {
-    messenger,
+    getControllerStateMock,
     getTransactionControllerStateMock,
+    messenger,
     publish,
     updateTransactionMock,
   } = getMessengerMock();
@@ -78,6 +85,28 @@ describe('Transaction Utils', () => {
     });
   });
 
+  describe('getTransactionData', () => {
+    it('returns transaction data', () => {
+      getControllerStateMock.mockReturnValue({
+        transactionData: {
+          [TRANSACTION_ID_MOCK]: TRANSACTION_DATA_MOCK,
+        },
+      });
+
+      const result = getTransactionData(TRANSACTION_ID_MOCK, messenger);
+      expect(result).toBe(TRANSACTION_DATA_MOCK);
+    });
+
+    it('returns undefined if transaction data not found', () => {
+      getControllerStateMock.mockReturnValue({
+        transactionData: {},
+      });
+
+      const result = getTransactionData(TRANSACTION_ID_MOCK, messenger);
+      expect(result).toBeUndefined();
+    });
+  });
+
   describe('pollTransactionChanges', () => {
     it('updates state for new transactions', () => {
       const updateTransactionDataMock = jest.fn();
diff --git a/packages/transaction-pay-controller/src/utils/transaction.ts b/packages/transaction-pay-controller/src/utils/transaction.ts
index 4b834be3f1d..13f38e765fc 100644
--- a/packages/transaction-pay-controller/src/utils/transaction.ts
+++ b/packages/transaction-pay-controller/src/utils/transaction.ts
@@ -40,6 +40,13 @@ export function getTransaction(
   );
 }
 
+/**
+ * Get transaction data for a specific transaction ID, if it exists.
+ *
+ * @param transactionId - ID of the transaction to get data for.
+ * @param messenger - Controller messenger.
+ * @returns Transaction data from the state, if it exists.
+ */
 export function getTransactionData(
   transactionId: string,
   messenger: TransactionPayControllerMessenger,

From fbfa2f689f0cf7a8be92d64e9ce500ba39886406 Mon Sep 17 00:00:00 2001
From: Matthew Walsh <matthew.walsh@consensys.net>
Date: Sun, 4 Jan 2026 22:10:35 +0000
Subject: [PATCH 03/13] Update source amount unit tests

Remove getTransactionData util.
---
 .../src/strategy/relay/relay-quotes.ts        | 30 +++++++++++--------
 .../transaction-pay-controller/src/types.ts   |  3 ++
 .../src/utils/quotes.test.ts                  |  1 +
 .../src/utils/quotes.ts                       | 10 +++++--
 .../src/utils/source-amounts.test.ts          | 19 ++++++++++++
 .../src/utils/source-amounts.ts               | 10 +++----
 .../src/utils/totals.ts                       |  6 ++--
 .../src/utils/transaction.test.ts             | 29 ------------------
 .../src/utils/transaction.ts                  | 19 ------------
 9 files changed, 56 insertions(+), 71 deletions(-)

diff --git a/packages/transaction-pay-controller/src/strategy/relay/relay-quotes.ts b/packages/transaction-pay-controller/src/strategy/relay/relay-quotes.ts
index 1ddd9b3b612..e9ae879f550 100644
--- a/packages/transaction-pay-controller/src/strategy/relay/relay-quotes.ts
+++ b/packages/transaction-pay-controller/src/strategy/relay/relay-quotes.ts
@@ -89,24 +89,28 @@ async function getSingleQuote(
     0,
   );
 
-  const { transactionData } = messenger.call(
-    'TransactionPayController:getState',
-  );
-  const isMaxAmount = transactionData[transaction.id]?.isMaxAmount;
+  const {
+    from,
+    isMaxAmount,
+    sourceChainId,
+    sourceTokenAddress,
+    sourceTokenAmount,
+    targetAmountMinimum,
+    targetChainId,
+    targetTokenAddress,
+  } = request;
 
   try {
     const body: RelayQuoteRequest = {
-      amount: isMaxAmount
-        ? request.sourceTokenAmount
-        : request.targetAmountMinimum,
-      destinationChainId: Number(request.targetChainId),
-      destinationCurrency: request.targetTokenAddress,
-      originChainId: Number(request.sourceChainId),
-      originCurrency: request.sourceTokenAddress,
-      recipient: request.from,
+      amount: isMaxAmount ? sourceTokenAmount : targetAmountMinimum,
+      destinationChainId: Number(targetChainId),
+      destinationCurrency: targetTokenAddress,
+      originChainId: Number(sourceChainId),
+      originCurrency: sourceTokenAddress,
+      recipient: from,
       slippageTolerance,
       tradeType: isMaxAmount ? 'EXACT_INPUT' : 'EXPECTED_OUTPUT',
-      user: request.from,
+      user: from,
     };
 
     await processTransactions(transaction, request, body, messenger);
diff --git a/packages/transaction-pay-controller/src/types.ts b/packages/transaction-pay-controller/src/types.ts
index 8120ba307b7..09b267f4f11 100644
--- a/packages/transaction-pay-controller/src/types.ts
+++ b/packages/transaction-pay-controller/src/types.ts
@@ -267,6 +267,9 @@ export type QuoteRequest = {
   /** Address of the user's account. */
   from: Hex;
 
+  /** Whether the transaction is a maximum amount transaction. */
+  isMaxAmount?: boolean;
+
   /** Balance of the source token in atomic format without factoring token decimals. */
   sourceBalanceRaw: string;
 
diff --git a/packages/transaction-pay-controller/src/utils/quotes.test.ts b/packages/transaction-pay-controller/src/utils/quotes.test.ts
index 4f5fb338744..4445c62301d 100644
--- a/packages/transaction-pay-controller/src/utils/quotes.test.ts
+++ b/packages/transaction-pay-controller/src/utils/quotes.test.ts
@@ -222,6 +222,7 @@ describe('Quotes Utils', () => {
         messenger,
         requests: [
           {
+            isMaxAmount: false,
             from: TRANSACTION_META_MOCK.txParams.from,
             sourceBalanceRaw: TRANSACTION_DATA_MOCK.paymentToken?.balanceRaw,
             sourceTokenAmount:
diff --git a/packages/transaction-pay-controller/src/utils/quotes.ts b/packages/transaction-pay-controller/src/utils/quotes.ts
index 1610965248e..9156c56c483 100644
--- a/packages/transaction-pay-controller/src/utils/quotes.ts
+++ b/packages/transaction-pay-controller/src/utils/quotes.ts
@@ -55,10 +55,11 @@ export async function updateQuotes(
 
   log('Updating quotes', { transactionId });
 
-  const { paymentToken, sourceAmounts, tokens } = transactionData;
+  const { isMaxAmount, paymentToken, sourceAmounts, tokens } = transactionData;
 
   const requests = buildQuoteRequests({
     from: transaction.txParams.from as Hex,
+    isMaxAmount: isMaxAmount ?? false,
     paymentToken,
     sourceAmounts,
     tokens,
@@ -77,8 +78,9 @@ export async function updateQuotes(
     );
 
     const totals = calculateTotals({
-      quotes: quotes as TransactionPayQuote<unknown>[],
+      isMaxAmount,
       messenger,
+      quotes: quotes as TransactionPayQuote<unknown>[],
       tokens,
       transaction,
     });
@@ -209,6 +211,7 @@ export async function refreshQuotes(
  *
  * @param request - Request parameters.
  * @param request.from - Address from which the transaction is sent.
+ * @param request.isMaxAmount - Whether the transaction is a maximum amount transaction.
  * @param request.paymentToken - Payment token used for the transaction.
  * @param request.sourceAmounts - Source amounts for the transaction.
  * @param request.tokens - Required tokens for the transaction.
@@ -217,12 +220,14 @@ export async function refreshQuotes(
  */
 function buildQuoteRequests({
   from,
+  isMaxAmount,
   paymentToken,
   sourceAmounts,
   tokens,
   transactionId,
 }: {
   from: Hex;
+  isMaxAmount: boolean;
   paymentToken: TransactionPaymentToken | undefined;
   sourceAmounts: TransactionPaySourceAmount[] | undefined;
   tokens: TransactionPayRequiredToken[];
@@ -239,6 +244,7 @@ function buildQuoteRequests({
 
     return {
       from,
+      isMaxAmount,
       sourceBalanceRaw: paymentToken.balanceRaw,
       sourceTokenAmount: sourceAmount.sourceAmountRaw,
       sourceChainId: paymentToken.chainId,
diff --git a/packages/transaction-pay-controller/src/utils/source-amounts.test.ts b/packages/transaction-pay-controller/src/utils/source-amounts.test.ts
index f8af32058c3..9612a79e032 100644
--- a/packages/transaction-pay-controller/src/utils/source-amounts.test.ts
+++ b/packages/transaction-pay-controller/src/utils/source-amounts.test.ts
@@ -163,6 +163,25 @@ describe('Source Amounts Utils', () => {
       expect(transactionData.sourceAmounts).toStrictEqual([]);
     });
 
+    it('uses payment token balance if isMaxAmount is true', () => {
+      const transactionData: TransactionData = {
+        isLoading: false,
+        isMaxAmount: true,
+        paymentToken: PAYMENT_TOKEN_MOCK,
+        tokens: [TRANSACTION_TOKEN_MOCK],
+      };
+
+      updateSourceAmounts(TRANSACTION_ID_MOCK, transactionData, messenger);
+
+      expect(transactionData.sourceAmounts).toStrictEqual([
+        {
+          sourceAmountHuman: PAYMENT_TOKEN_MOCK.balanceHuman,
+          sourceAmountRaw: PAYMENT_TOKEN_MOCK.balanceRaw,
+          targetTokenAddress: TRANSACTION_TOKEN_MOCK.address,
+        },
+      ]);
+    });
+
     it('does nothing if no payment token', () => {
       const transactionData: TransactionData = {
         isLoading: false,
diff --git a/packages/transaction-pay-controller/src/utils/source-amounts.ts b/packages/transaction-pay-controller/src/utils/source-amounts.ts
index 339b476f523..f98cd422c37 100644
--- a/packages/transaction-pay-controller/src/utils/source-amounts.ts
+++ b/packages/transaction-pay-controller/src/utils/source-amounts.ts
@@ -2,7 +2,7 @@ import { createModuleLogger } from '@metamask/utils';
 import { BigNumber } from 'bignumber.js';
 
 import { getTokenFiatRate } from './token';
-import { getTransaction, getTransactionData } from './transaction';
+import { getTransaction } from './transaction';
 import type {
   TransactionPayControllerMessenger,
   TransactionPaymentToken,
@@ -35,7 +35,7 @@ export function updateSourceAmounts(
     return;
   }
 
-  const { paymentToken, tokens } = transactionData;
+  const { isMaxAmount, paymentToken, tokens } = transactionData;
 
   if (!tokens.length || !paymentToken) {
     return;
@@ -48,6 +48,7 @@ export function updateSourceAmounts(
         singleToken,
         messenger,
         transactionId,
+        isMaxAmount ?? false,
       ),
     )
     .filter(Boolean) as TransactionPaySourceAmount[];
@@ -64,6 +65,7 @@ export function updateSourceAmounts(
  * @param token - Target token to cover.
  * @param messenger - Controller messenger.
  * @param transactionId - ID of the transaction.
+ * @param isMaxAmount - Whether the transaction is a maximum amount transaction.
  * @returns The source amount or undefined if calculation failed.
  */
 function calculateSourceAmount(
@@ -71,6 +73,7 @@ function calculateSourceAmount(
   token: TransactionPayRequiredToken,
   messenger: TransactionPayControllerMessenger,
   transactionId: string,
+  isMaxAmount: boolean,
 ): TransactionPaySourceAmount | undefined {
   const paymentTokenFiatRate = getTokenFiatRate(
     messenger,
@@ -119,9 +122,6 @@ function calculateSourceAmount(
     return undefined;
   }
 
-  const transactionData = getTransactionData(transactionId, messenger);
-  const isMaxAmount = transactionData?.isMaxAmount ?? false;
-
   if (isMaxAmount) {
     return {
       sourceAmountHuman: paymentToken.balanceHuman,
diff --git a/packages/transaction-pay-controller/src/utils/totals.ts b/packages/transaction-pay-controller/src/utils/totals.ts
index 9efcf38ece6..f2c9085ffa7 100644
--- a/packages/transaction-pay-controller/src/utils/totals.ts
+++ b/packages/transaction-pay-controller/src/utils/totals.ts
@@ -2,7 +2,6 @@ import type { TransactionMeta } from '@metamask/transaction-controller';
 import { BigNumber } from 'bignumber.js';
 
 import { calculateTransactionGasCost } from './gas';
-import { getTransactionData } from './transaction';
 import type {
   Amount,
   FiatValue,
@@ -16,6 +15,7 @@ import type {
  * Calculate totals for a list of quotes and tokens.
  *
  * @param request - Request parameters.
+ * @param request.isMaxAmount - Whether the transaction is a maximum amount transaction.
  * @param request.quotes - List of bridge quotes.
  * @param request.messenger - Controller messenger.
  * @param request.tokens - List of required tokens.
@@ -23,11 +23,13 @@ import type {
  * @returns The calculated totals in USD and fiat currency.
  */
 export function calculateTotals({
+  isMaxAmount,
   quotes,
   messenger,
   tokens,
   transaction,
 }: {
+  isMaxAmount?: boolean;
   quotes: TransactionPayQuote<unknown>[];
   messenger: TransactionPayControllerMessenger;
   tokens: TransactionPayRequiredToken[];
@@ -61,8 +63,6 @@ export function calculateTotals({
     (singleToken) => !singleToken.skipIfBalance,
   );
 
-  const transactionData = getTransactionData(transaction.id, messenger);
-  const isMaxAmount = transactionData?.isMaxAmount ?? false;
   const amountFiat = sumProperty(quoteTokens, (token) => token.amountFiat);
   const amountUsd = sumProperty(quoteTokens, (token) => token.amountUsd);
 
diff --git a/packages/transaction-pay-controller/src/utils/transaction.test.ts b/packages/transaction-pay-controller/src/utils/transaction.test.ts
index 48716943906..ce7145bbd27 100644
--- a/packages/transaction-pay-controller/src/utils/transaction.test.ts
+++ b/packages/transaction-pay-controller/src/utils/transaction.test.ts
@@ -12,7 +12,6 @@ import {
   FINALIZED_STATUSES,
   collectTransactionIds,
   getTransaction,
-  getTransactionData,
   pollTransactionChanges,
   updateTransaction,
   waitForTransactionConfirmed,
@@ -42,15 +41,9 @@ const TRANSCTION_TOKEN_REQUIRED_MOCK = {
   balanceUsd: '5',
 } as TransactionPayRequiredToken;
 
-const TRANSACTION_DATA_MOCK = {
-  isLoading: false,
-  tokens: [TRANSCTION_TOKEN_REQUIRED_MOCK],
-} as TransactionData;
-
 describe('Transaction Utils', () => {
   const parseRequiredTokensMock = jest.mocked(parseRequiredTokens);
   const {
-    getControllerStateMock,
     getTransactionControllerStateMock,
     messenger,
     publish,
@@ -85,28 +78,6 @@ describe('Transaction Utils', () => {
     });
   });
 
-  describe('getTransactionData', () => {
-    it('returns transaction data', () => {
-      getControllerStateMock.mockReturnValue({
-        transactionData: {
-          [TRANSACTION_ID_MOCK]: TRANSACTION_DATA_MOCK,
-        },
-      });
-
-      const result = getTransactionData(TRANSACTION_ID_MOCK, messenger);
-      expect(result).toBe(TRANSACTION_DATA_MOCK);
-    });
-
-    it('returns undefined if transaction data not found', () => {
-      getControllerStateMock.mockReturnValue({
-        transactionData: {},
-      });
-
-      const result = getTransactionData(TRANSACTION_ID_MOCK, messenger);
-      expect(result).toBeUndefined();
-    });
-  });
-
   describe('pollTransactionChanges', () => {
     it('updates state for new transactions', () => {
       const updateTransactionDataMock = jest.fn();
diff --git a/packages/transaction-pay-controller/src/utils/transaction.ts b/packages/transaction-pay-controller/src/utils/transaction.ts
index 13f38e765fc..7a5d14d2285 100644
--- a/packages/transaction-pay-controller/src/utils/transaction.ts
+++ b/packages/transaction-pay-controller/src/utils/transaction.ts
@@ -7,7 +7,6 @@ import { cloneDeep } from 'lodash';
 import { parseRequiredTokens } from './required-tokens';
 import { projectLogger } from '../logger';
 import type {
-  TransactionData,
   TransactionPayControllerMessenger,
   UpdateTransactionDataCallback,
 } from '../types';
@@ -40,24 +39,6 @@ export function getTransaction(
   );
 }
 
-/**
- * Get transaction data for a specific transaction ID, if it exists.
- *
- * @param transactionId - ID of the transaction to get data for.
- * @param messenger - Controller messenger.
- * @returns Transaction data from the state, if it exists.
- */
-export function getTransactionData(
-  transactionId: string,
-  messenger: TransactionPayControllerMessenger,
-): TransactionData | undefined {
-  const { transactionData } = messenger.call(
-    'TransactionPayController:getState',
-  );
-
-  return transactionData[transactionId];
-}
-
 /**
  * Poll for transaction changes and update the transaction data accordingly.
  *

From fc9a41de626c6a866a57c39c0ba3b4736094aae9 Mon Sep 17 00:00:00 2001
From: Matthew Walsh <matthew.walsh@consensys.net>
Date: Sun, 4 Jan 2026 22:19:36 +0000
Subject: [PATCH 04/13] Update totals unit tests

---
 .../src/utils/totals.test.ts                        | 13 +++++++++++++
 1 file changed, 13 insertions(+)

diff --git a/packages/transaction-pay-controller/src/utils/totals.test.ts b/packages/transaction-pay-controller/src/utils/totals.test.ts
index 98c5891acde..d01b04184ba 100644
--- a/packages/transaction-pay-controller/src/utils/totals.test.ts
+++ b/packages/transaction-pay-controller/src/utils/totals.test.ts
@@ -150,6 +150,19 @@ describe('Totals Utils', () => {
       expect(result.total.usd).toBe('51.08');
     });
 
+    it('returns adjusted total when isMaxAmount is true', () => {
+      const result = calculateTotals({
+        isMaxAmount: true,
+        quotes: [QUOTE_1_MOCK, QUOTE_2_MOCK],
+        tokens: [TOKEN_1_MOCK, TOKEN_2_MOCK],
+        messenger: MESSENGER_MOCK,
+        transaction: TRANSACTION_META_MOCK,
+      });
+
+      expect(result.total.fiat).toBe('50.88');
+      expect(result.total.usd).toBe('56.34');
+    });
+
     it('returns total excluding token amount not in quote', () => {
       const result = calculateTotals({
         quotes: [QUOTE_1_MOCK, QUOTE_2_MOCK],

From 8f50b578143a2095f227e3b28988d841ead021f6 Mon Sep 17 00:00:00 2001
From: Matthew Walsh <matthew.walsh@consensys.net>
Date: Sun, 4 Jan 2026 22:49:04 +0000
Subject: [PATCH 05/13] Add relay quotes unit tests

---
 .../src/strategy/relay/relay-quotes.test.ts   | 23 +++++++++++++++++++
 .../src/strategy/relay/relay-quotes.ts        |  5 ++--
 2 files changed, 26 insertions(+), 2 deletions(-)

diff --git a/packages/transaction-pay-controller/src/strategy/relay/relay-quotes.test.ts b/packages/transaction-pay-controller/src/strategy/relay/relay-quotes.test.ts
index 9a95aa1e286..0055c331f5e 100644
--- a/packages/transaction-pay-controller/src/strategy/relay/relay-quotes.test.ts
+++ b/packages/transaction-pay-controller/src/strategy/relay/relay-quotes.test.ts
@@ -255,6 +255,29 @@ describe('Relay Quotes Utils', () => {
       );
     });
 
+    it('sends request with EXACT_INPUT trade type when isMaxAmount is true', async () => {
+      successfulFetchMock.mockResolvedValue({
+        json: async () => QUOTE_MOCK,
+      } as never);
+
+      await getRelayQuotes({
+        messenger,
+        requests: [{ ...QUOTE_REQUEST_MOCK, isMaxAmount: true }],
+        transaction: TRANSACTION_META_MOCK,
+      });
+
+      const body = JSON.parse(
+        successfulFetchMock.mock.calls[0][1]?.body as string,
+      );
+
+      expect(body).toStrictEqual(
+        expect.objectContaining({
+          amount: QUOTE_REQUEST_MOCK.sourceTokenAmount,
+          tradeType: 'EXACT_INPUT',
+        }),
+      );
+    });
+
     it('includes transactions in request', async () => {
       successfulFetchMock.mockResolvedValue({
         json: async () => QUOTE_MOCK,
diff --git a/packages/transaction-pay-controller/src/strategy/relay/relay-quotes.ts b/packages/transaction-pay-controller/src/strategy/relay/relay-quotes.ts
index e9ae879f550..4d9d3310199 100644
--- a/packages/transaction-pay-controller/src/strategy/relay/relay-quotes.ts
+++ b/packages/transaction-pay-controller/src/strategy/relay/relay-quotes.ts
@@ -152,12 +152,13 @@ async function processTransactions(
   messenger: TransactionPayControllerMessenger,
 ): Promise<void> {
   const { nestedTransactions, txParams } = transaction;
+  const { isMaxAmount, targetChainId } = request;
   const data = txParams?.data as Hex | undefined;
 
   const singleData =
     nestedTransactions?.length === 1 ? nestedTransactions[0].data : data;
 
-  const isHypercore = request.targetChainId === CHAIN_ID_HYPERCORE;
+  const isHypercore = targetChainId === CHAIN_ID_HYPERCORE;
 
   const isTokenTransfer =
     !isHypercore && Boolean(singleData?.startsWith(TOKEN_TRANSFER_FOUR_BYTE));
@@ -168,7 +169,7 @@ async function processTransactions(
     log('Updating recipient as token transfer', requestBody.recipient);
   }
 
-  const skipDelegation = isTokenTransfer || isHypercore;
+  const skipDelegation = isTokenTransfer || isHypercore || isMaxAmount;
 
   if (skipDelegation) {
     log('Skipping delegation as token transfer or Hypercore deposit');

From 62f2ed625f25818875145fbc9e9946c7c6b96691 Mon Sep 17 00:00:00 2001
From: Matthew Walsh <matthew.walsh@consensys.net>
Date: Tue, 6 Jan 2026 16:29:26 +0000
Subject: [PATCH 06/13] Rename method and action

---
 .../src/TransactionPayController.ts                         | 6 +++---
 packages/transaction-pay-controller/src/index.ts            | 2 +-
 packages/transaction-pay-controller/src/types.ts            | 6 +++---
 3 files changed, 7 insertions(+), 7 deletions(-)

diff --git a/packages/transaction-pay-controller/src/TransactionPayController.ts b/packages/transaction-pay-controller/src/TransactionPayController.ts
index b4b240a61d9..a4aa4efa44d 100644
--- a/packages/transaction-pay-controller/src/TransactionPayController.ts
+++ b/packages/transaction-pay-controller/src/TransactionPayController.ts
@@ -81,7 +81,7 @@ export class TransactionPayController extends BaseController<
     });
   }
 
-  setIsMax(transactionId: string, isMaxAmount: boolean): void {
+  setIsMaxAmount(transactionId: string, isMaxAmount: boolean): void {
     this.#updateTransactionData(transactionId, (transactionData) => {
       transactionData.isMaxAmount = isMaxAmount;
     });
@@ -158,8 +158,8 @@ export class TransactionPayController extends BaseController<
     );
 
     this.messenger.registerActionHandler(
-      'TransactionPayController:setIsMax',
-      this.setIsMax.bind(this),
+      'TransactionPayController:setIsMaxAmount',
+      this.setIsMaxAmount.bind(this),
     );
   }
 }
diff --git a/packages/transaction-pay-controller/src/index.ts b/packages/transaction-pay-controller/src/index.ts
index 380e35a42d2..d3cb83c35f3 100644
--- a/packages/transaction-pay-controller/src/index.ts
+++ b/packages/transaction-pay-controller/src/index.ts
@@ -6,7 +6,7 @@ export type {
   TransactionPayControllerGetStrategyAction,
   TransactionPayControllerMessenger,
   TransactionPayControllerOptions,
-  TransactionPayControllerSetIsMaxAction,
+  TransactionPayControllerSetIsMaxAmountAction,
   TransactionPayControllerState,
   TransactionPayControllerStateChangeEvent,
   TransactionPayControllerUpdatePaymentTokenAction,
diff --git a/packages/transaction-pay-controller/src/types.ts b/packages/transaction-pay-controller/src/types.ts
index 09b267f4f11..ea9d4db62a4 100644
--- a/packages/transaction-pay-controller/src/types.ts
+++ b/packages/transaction-pay-controller/src/types.ts
@@ -86,8 +86,8 @@ export type TransactionPayControllerUpdatePaymentTokenAction = {
 };
 
 /** Action to set the max amount flag for a transaction. */
-export type TransactionPayControllerSetIsMaxAction = {
-  type: `${typeof CONTROLLER_NAME}:setIsMax`;
+export type TransactionPayControllerSetIsMaxAmountAction = {
+  type: `${typeof CONTROLLER_NAME}:setIsMaxAmount`;
   handler: (transactionId: string, isMaxAmount: boolean) => void;
 };
 
@@ -101,7 +101,7 @@ export type TransactionPayControllerActions =
   | TransactionPayControllerGetDelegationTransactionAction
   | TransactionPayControllerGetStateAction
   | TransactionPayControllerGetStrategyAction
-  | TransactionPayControllerSetIsMaxAction
+  | TransactionPayControllerSetIsMaxAmountAction
   | TransactionPayControllerUpdatePaymentTokenAction;
 
 export type TransactionPayControllerEvents =

From 591c431461af1c52f37552e07a5952de535455f2 Mon Sep 17 00:00:00 2001
From: Matthew Walsh <matthew.walsh@consensys.net>
Date: Tue, 6 Jan 2026 17:57:16 +0000
Subject: [PATCH 07/13] Fix coverage

---
 .../src/TransactionPayController.test.ts      | 12 ++++++++++
 .../src/TransactionPayController.ts           | 22 +++++++++----------
 .../src/strategy/relay/types.ts               |  2 +-
 .../src/utils/transaction.test.ts             |  2 +-
 4 files changed, 25 insertions(+), 13 deletions(-)

diff --git a/packages/transaction-pay-controller/src/TransactionPayController.test.ts b/packages/transaction-pay-controller/src/TransactionPayController.test.ts
index 80fece81294..82232be1a13 100644
--- a/packages/transaction-pay-controller/src/TransactionPayController.test.ts
+++ b/packages/transaction-pay-controller/src/TransactionPayController.test.ts
@@ -74,6 +74,18 @@ describe('TransactionPayController', () => {
     });
   });
 
+  describe('setIsMaxAmount', () => {
+    it('updates state', () => {
+      const controller = createController();
+
+      controller.setIsMaxAmount(TRANSACTION_ID_MOCK, true);
+
+      expect(
+        controller.state.transactionData[TRANSACTION_ID_MOCK].isMaxAmount,
+      ).toBe(true);
+    });
+  });
+
   describe('getStrategy Action', () => {
     it('returns relay if no callback', async () => {
       createController();
diff --git a/packages/transaction-pay-controller/src/TransactionPayController.ts b/packages/transaction-pay-controller/src/TransactionPayController.ts
index a4aa4efa44d..9bba57d98d8 100644
--- a/packages/transaction-pay-controller/src/TransactionPayController.ts
+++ b/packages/transaction-pay-controller/src/TransactionPayController.ts
@@ -74,6 +74,12 @@ export class TransactionPayController extends BaseController<
     });
   }
 
+  setIsMaxAmount(transactionId: string, isMaxAmount: boolean): void {
+    this.#updateTransactionData(transactionId, (transactionData) => {
+      transactionData.isMaxAmount = isMaxAmount;
+    });
+  }
+
   updatePaymentToken(request: UpdatePaymentTokenRequest): void {
     updatePaymentToken(request, {
       messenger: this.messenger,
@@ -81,12 +87,6 @@ export class TransactionPayController extends BaseController<
     });
   }
 
-  setIsMaxAmount(transactionId: string, isMaxAmount: boolean): void {
-    this.#updateTransactionData(transactionId, (transactionData) => {
-      transactionData.isMaxAmount = isMaxAmount;
-    });
-  }
-
   #removeTransactionData(transactionId: string): void {
     this.update((state) => {
       delete state.transactionData[transactionId];
@@ -123,7 +123,7 @@ export class TransactionPayController extends BaseController<
       const isTokensUpdated = current.tokens !== originalTokens;
       const isIsMaxUpdated = current.isMaxAmount !== originalIsMaxAmount;
 
-      if (isPaymentTokenUpdated || isTokensUpdated || isIsMaxUpdated) {
+      if (isPaymentTokenUpdated || isIsMaxUpdated || isTokensUpdated) {
         updateSourceAmounts(transactionId, current as never, this.messenger);
 
         shouldUpdateQuotes = true;
@@ -153,13 +153,13 @@ export class TransactionPayController extends BaseController<
     );
 
     this.messenger.registerActionHandler(
-      'TransactionPayController:updatePaymentToken',
-      this.updatePaymentToken.bind(this),
+      'TransactionPayController:setIsMaxAmount',
+      this.setIsMaxAmount.bind(this),
     );
 
     this.messenger.registerActionHandler(
-      'TransactionPayController:setIsMaxAmount',
-      this.setIsMaxAmount.bind(this),
+      'TransactionPayController:updatePaymentToken',
+      this.updatePaymentToken.bind(this),
     );
   }
 }
diff --git a/packages/transaction-pay-controller/src/strategy/relay/types.ts b/packages/transaction-pay-controller/src/strategy/relay/types.ts
index 2eb031ee260..28cb5677eb8 100644
--- a/packages/transaction-pay-controller/src/strategy/relay/types.ts
+++ b/packages/transaction-pay-controller/src/strategy/relay/types.ts
@@ -17,7 +17,7 @@ export type RelayQuoteRequest = {
   recipient: Hex;
   refundTo?: Hex;
   slippageTolerance?: string;
-  tradeType: 'EXPECTED_OUTPUT' | 'EXACT_OUTPUT' | 'EXACT_INPUT';
+  tradeType: 'EXACT_INPUT' | 'EXACT_OUTPUT' | 'EXPECTED_OUTPUT';
   txs?: {
     to: Hex;
     data: Hex;
diff --git a/packages/transaction-pay-controller/src/utils/transaction.test.ts b/packages/transaction-pay-controller/src/utils/transaction.test.ts
index ce7145bbd27..bd6f7ddb6ee 100644
--- a/packages/transaction-pay-controller/src/utils/transaction.test.ts
+++ b/packages/transaction-pay-controller/src/utils/transaction.test.ts
@@ -44,8 +44,8 @@ const TRANSCTION_TOKEN_REQUIRED_MOCK = {
 describe('Transaction Utils', () => {
   const parseRequiredTokensMock = jest.mocked(parseRequiredTokens);
   const {
-    getTransactionControllerStateMock,
     messenger,
+    getTransactionControllerStateMock,
     publish,
     updateTransactionMock,
   } = getMessengerMock();

From e44ac8b61080783740c8da31e9c690ea96b2a3b2 Mon Sep 17 00:00:00 2001
From: Matthew Walsh <matthew.walsh@consensys.net>
Date: Tue, 6 Jan 2026 18:10:04 +0000
Subject: [PATCH 08/13] Update changelog

---
 packages/transaction-pay-controller/CHANGELOG.md | 7 +++++++
 1 file changed, 7 insertions(+)

diff --git a/packages/transaction-pay-controller/CHANGELOG.md b/packages/transaction-pay-controller/CHANGELOG.md
index 6db47aa063a..90a62aaedbc 100644
--- a/packages/transaction-pay-controller/CHANGELOG.md
+++ b/packages/transaction-pay-controller/CHANGELOG.md
@@ -7,6 +7,13 @@ and this project adheres to [Semantic Versioning](https://semver.org/spec/v2.0.0
 
 ## [Unreleased]
 
+### Added
+
+- Add `TransactionPayController:setIsMaxAmount` messenger action to set max amount flag for a transaction ([#7562](https://github.com/MetaMask/core/pull/7562))
+  - Add `isMaxAmount` property to `TransactionData` type.
+  - Update Relay quote requests to use `EXACT_INPUT` trade type when max amount is selected.
+  - Update totals calculation to account for max amount selection.
+
 ### Changed
 
 - Bump `@metamask/controller-utils` from `^11.17.0` to `^11.18.0` ([#7583](https://github.com/MetaMask/core/pull/7583))

From f10dd311248fb1ef595e19ae8a872aed8be71b65 Mon Sep 17 00:00:00 2001
From: Matthew Walsh <matthew.walsh@consensys.net>
Date: Wed, 7 Jan 2026 23:53:32 +0000
Subject: [PATCH 09/13] Add target amount

---
 packages/transaction-controller/src/types.ts        |  3 +++
 .../src/strategy/bridge/bridge-quotes.ts            |  1 +
 .../src/strategy/relay/relay-quotes.ts              |  9 ++++++++-
 .../src/strategy/relay/types.ts                     |  1 +
 .../src/strategy/test/TestStrategy.ts               |  6 ++++++
 packages/transaction-pay-controller/src/types.ts    |  6 ++++++
 .../transaction-pay-controller/src/utils/quotes.ts  |  1 +
 .../transaction-pay-controller/src/utils/totals.ts  | 13 +++++--------
 8 files changed, 31 insertions(+), 9 deletions(-)

diff --git a/packages/transaction-controller/src/types.ts b/packages/transaction-controller/src/types.ts
index 9d42d444f95..2d6aaf3d565 100644
--- a/packages/transaction-controller/src/types.ts
+++ b/packages/transaction-controller/src/types.ts
@@ -2071,6 +2071,9 @@ export type MetamaskPayMetadata = {
   /** Total network fee in fiat currency, including the original and bridge transactions. */
   networkFeeFiat?: string;
 
+  /** Total amount of target token provided in fiat currency. */
+  targetFiat?: string;
+
   /** Address of the payment token that the transaction funds were sourced from. */
   tokenAddress?: Hex;
 
diff --git a/packages/transaction-pay-controller/src/strategy/bridge/bridge-quotes.ts b/packages/transaction-pay-controller/src/strategy/bridge/bridge-quotes.ts
index d30aa73e98a..a82e6e2bbe1 100644
--- a/packages/transaction-pay-controller/src/strategy/bridge/bridge-quotes.ts
+++ b/packages/transaction-pay-controller/src/strategy/bridge/bridge-quotes.ts
@@ -554,6 +554,7 @@ function normalizeQuote(
     original: quote,
     request,
     sourceAmount,
+    targetAmount,
     strategy: TransactionPayStrategy.Bridge,
   };
 }
diff --git a/packages/transaction-pay-controller/src/strategy/relay/relay-quotes.ts b/packages/transaction-pay-controller/src/strategy/relay/relay-quotes.ts
index 4d9d3310199..6e6feb4cacb 100644
--- a/packages/transaction-pay-controller/src/strategy/relay/relay-quotes.ts
+++ b/packages/transaction-pay-controller/src/strategy/relay/relay-quotes.ts
@@ -275,7 +275,7 @@ async function normalizeQuote(
 ): Promise<TransactionPayQuote<RelayQuote>> {
   const { messenger } = fullRequest;
   const { details } = quote;
-  const { currencyIn } = details;
+  const { currencyIn, currencyOut } = details;
 
   const { usdToFiatRate } = getFiatRates(messenger, request);
 
@@ -306,6 +306,12 @@ async function normalizeQuote(
     ...getFiatValueFromUsd(new BigNumber(currencyIn.amountUsd), usdToFiatRate),
   };
 
+  const targetAmount: Amount = {
+    human: currencyOut.amountFormatted,
+    raw: currencyOut.amount,
+    ...getFiatValueFromUsd(new BigNumber(currencyOut.amountUsd), usdToFiatRate),
+  };
+
   const metamask = {
     gasLimits,
   };
@@ -325,6 +331,7 @@ async function normalizeQuote(
     },
     request,
     sourceAmount,
+    targetAmount,
     strategy: TransactionPayStrategy.Relay,
   };
 }
diff --git a/packages/transaction-pay-controller/src/strategy/relay/types.ts b/packages/transaction-pay-controller/src/strategy/relay/types.ts
index 28cb5677eb8..4883e2837cf 100644
--- a/packages/transaction-pay-controller/src/strategy/relay/types.ts
+++ b/packages/transaction-pay-controller/src/strategy/relay/types.ts
@@ -38,6 +38,7 @@ export type RelayQuote = {
       };
     };
     currencyOut: {
+      amount: string;
       amountFormatted: string;
       amountUsd: string;
       currency: {
diff --git a/packages/transaction-pay-controller/src/strategy/test/TestStrategy.ts b/packages/transaction-pay-controller/src/strategy/test/TestStrategy.ts
index b0ca2cc7359..06b470bcb8e 100644
--- a/packages/transaction-pay-controller/src/strategy/test/TestStrategy.ts
+++ b/packages/transaction-pay-controller/src/strategy/test/TestStrategy.ts
@@ -54,6 +54,12 @@ export class TestStrategy implements PayStrategy<void> {
           raw: '456000',
           usd: '4.56',
         },
+        targetAmount: {
+          human: '5.67',
+          fiat: '5.67',
+          raw: '567000',
+          usd: '5.67',
+        },
         strategy: TransactionPayStrategy.Test,
       },
     ];
diff --git a/packages/transaction-pay-controller/src/types.ts b/packages/transaction-pay-controller/src/types.ts
index ea9d4db62a4..8539a6e15ff 100644
--- a/packages/transaction-pay-controller/src/types.ts
+++ b/packages/transaction-pay-controller/src/types.ts
@@ -335,6 +335,9 @@ export type TransactionPayQuote<OriginalQuote> = {
 
   /** Name of the strategy used to retrieve the quote. */
   strategy: TransactionPayStrategy;
+
+  /** Amount of target token provided. */
+  targetAmount: Amount;
 };
 
 /** Request to get quotes for a transaction. */
@@ -428,6 +431,9 @@ export type TransactionPayTotals = {
   /** Total amount of source token required. */
   sourceAmount: Amount;
 
+  /** Total amount of target token provided. */
+  targetAmount: Amount;
+
   /** Overall total cost for the target transaction and all quotes. */
   total: FiatValue;
 };
diff --git a/packages/transaction-pay-controller/src/utils/quotes.ts b/packages/transaction-pay-controller/src/utils/quotes.ts
index 9156c56c483..a242607fbf7 100644
--- a/packages/transaction-pay-controller/src/utils/quotes.ts
+++ b/packages/transaction-pay-controller/src/utils/quotes.ts
@@ -150,6 +150,7 @@ function syncTransaction({
         bridgeFeeFiat: totals.fees.provider.usd,
         chainId: paymentToken.chainId,
         networkFeeFiat: totals.fees.sourceNetwork.estimate.usd,
+        targetFiat: totals.targetAmount.usd,
         tokenAddress: paymentToken.address,
         totalFiat: totals.total.usd,
       };
diff --git a/packages/transaction-pay-controller/src/utils/totals.ts b/packages/transaction-pay-controller/src/utils/totals.ts
index f2c9085ffa7..7588857a9cb 100644
--- a/packages/transaction-pay-controller/src/utils/totals.ts
+++ b/packages/transaction-pay-controller/src/utils/totals.ts
@@ -58,6 +58,7 @@ export function calculateTotals({
     : transactionNetworkFee;
 
   const sourceAmount = sumAmounts(quotes.map((quote) => quote.sourceAmount));
+  const targetAmount = sumAmounts(quotes.map((quote) => quote.targetAmount));
 
   const quoteTokens = tokens.filter(
     (singleToken) => !singleToken.skipIfBalance,
@@ -65,23 +66,18 @@ export function calculateTotals({
 
   const amountFiat = sumProperty(quoteTokens, (token) => token.amountFiat);
   const amountUsd = sumProperty(quoteTokens, (token) => token.amountUsd);
+  const hasQuotes = quotes.length > 0;
 
   const totalFiat = new BigNumber(providerFee.fiat)
     .plus(sourceNetworkFeeEstimate.fiat)
     .plus(targetNetworkFee.fiat)
-    .plus(amountFiat)
-    .plus(isMaxAmount ? sourceAmount.fiat : 0)
-    .minus(isMaxAmount ? amountFiat : 0)
-    .minus(isMaxAmount ? providerFee.fiat : 0)
+    .plus(isMaxAmount && hasQuotes ? targetAmount.fiat : amountFiat)
     .toString(10);
 
   const totalUsd = new BigNumber(providerFee.usd)
     .plus(sourceNetworkFeeEstimate.usd)
     .plus(targetNetworkFee.usd)
-    .plus(amountUsd)
-    .plus(isMaxAmount ? sourceAmount.usd : 0)
-    .minus(isMaxAmount ? amountUsd : 0)
-    .minus(isMaxAmount ? providerFee.usd : 0)
+    .plus(isMaxAmount && hasQuotes ? targetAmount.usd : amountUsd)
     .toString(10);
 
   const estimatedDuration = Number(
@@ -109,6 +105,7 @@ export function calculateTotals({
       targetNetwork: targetNetworkFee,
     },
     sourceAmount,
+    targetAmount,
     total: {
       fiat: totalFiat,
       usd: totalUsd,

From 75f04502525f484e4367a0c76bfbd18e301a2806 Mon Sep 17 00:00:00 2001
From: Matthew Walsh <matthew.walsh@consensys.net>
Date: Thu, 8 Jan 2026 09:56:15 +0000
Subject: [PATCH 10/13] Fix unit tests

---
 .../src/strategy/test/TestStrategy.test.ts       |  6 ++++++
 .../src/utils/quotes.test.ts                     |  7 +++++++
 .../src/utils/totals.test.ts                     | 16 ++++++++++++++--
 3 files changed, 27 insertions(+), 2 deletions(-)

diff --git a/packages/transaction-pay-controller/src/strategy/test/TestStrategy.test.ts b/packages/transaction-pay-controller/src/strategy/test/TestStrategy.test.ts
index 3207baf5899..a6ed67f3c1a 100644
--- a/packages/transaction-pay-controller/src/strategy/test/TestStrategy.test.ts
+++ b/packages/transaction-pay-controller/src/strategy/test/TestStrategy.test.ts
@@ -67,6 +67,12 @@ describe('TestStrategy', () => {
             usd: expect.any(String),
           },
           strategy: TransactionPayStrategy.Test,
+          targetAmount: {
+            fiat: expect.any(String),
+            human: expect.any(String),
+            raw: expect.any(String),
+            usd: expect.any(String),
+          },
         },
       ]);
     });
diff --git a/packages/transaction-pay-controller/src/utils/quotes.test.ts b/packages/transaction-pay-controller/src/utils/quotes.test.ts
index 4445c62301d..a247cef45d1 100644
--- a/packages/transaction-pay-controller/src/utils/quotes.test.ts
+++ b/packages/transaction-pay-controller/src/utils/quotes.test.ts
@@ -73,6 +73,12 @@ const TOTALS_MOCK = {
       },
     },
   },
+  targetAmount: {
+    fiat: '5.67',
+    human: '5.67',
+    raw: '567000',
+    usd: '6.78',
+  },
   total: {
     fiat: '1.23',
     usd: '4.56',
@@ -301,6 +307,7 @@ describe('Quotes Utils', () => {
           bridgeFeeFiat: TOTALS_MOCK.fees.provider.usd,
           chainId: TRANSACTION_DATA_MOCK.paymentToken?.chainId,
           networkFeeFiat: TOTALS_MOCK.fees.sourceNetwork.estimate.usd,
+          targetFiat: TOTALS_MOCK.targetAmount.usd,
           tokenAddress: TRANSACTION_DATA_MOCK.paymentToken?.address,
           totalFiat: TOTALS_MOCK.total.usd,
         },
diff --git a/packages/transaction-pay-controller/src/utils/totals.test.ts b/packages/transaction-pay-controller/src/utils/totals.test.ts
index d01b04184ba..59c1beb6a59 100644
--- a/packages/transaction-pay-controller/src/utils/totals.test.ts
+++ b/packages/transaction-pay-controller/src/utils/totals.test.ts
@@ -53,6 +53,12 @@ const QUOTE_1_MOCK: TransactionPayQuote<unknown> = {
     usd: '8.88',
   },
   strategy: TransactionPayStrategy.Test,
+  targetAmount: {
+    human: '9.99',
+    fiat: '9.99',
+    raw: '999000000000000',
+    usd: '10.10',
+  },
 };
 
 const TOKEN_1_MOCK = {
@@ -105,6 +111,12 @@ const QUOTE_2_MOCK: TransactionPayQuote<unknown> = {
     usd: '14.14',
   },
   strategy: TransactionPayStrategy.Test,
+  targetAmount: {
+    human: '15.15',
+    fiat: '15.15',
+    raw: '1515000000000000',
+    usd: '16.16',
+  },
 };
 
 const TRANSACTION_META_MOCK = {} as TransactionMeta;
@@ -159,8 +171,8 @@ describe('Totals Utils', () => {
         transaction: TRANSACTION_META_MOCK,
       });
 
-      expect(result.total.fiat).toBe('50.88');
-      expect(result.total.usd).toBe('56.34');
+      expect(result.total.fiat).toBe('64');
+      expect(result.total.usd).toBe('70.68');
     });
 
     it('returns total excluding token amount not in quote', () => {

From 349de900603847c5f6284bd55ae9d1efb583494e Mon Sep 17 00:00:00 2001
From: Matthew Walsh <matthew.walsh@consensys.net>
Date: Thu, 8 Jan 2026 10:50:48 +0000
Subject: [PATCH 11/13] Add unit tests

---
 .../transaction-pay-controller/CHANGELOG.md   |  4 +++-
 .../src/strategy/bridge/bridge-quotes.test.ts | 14 ++++++++++++
 .../src/strategy/relay/relay-quotes.test.ts   | 22 +++++++++++++++++++
 3 files changed, 39 insertions(+), 1 deletion(-)

diff --git a/packages/transaction-pay-controller/CHANGELOG.md b/packages/transaction-pay-controller/CHANGELOG.md
index 90a62aaedbc..fe01d1da3c6 100644
--- a/packages/transaction-pay-controller/CHANGELOG.md
+++ b/packages/transaction-pay-controller/CHANGELOG.md
@@ -9,8 +9,10 @@ and this project adheres to [Semantic Versioning](https://semver.org/spec/v2.0.0
 
 ### Added
 
-- Add `TransactionPayController:setIsMaxAmount` messenger action to set max amount flag for a transaction ([#7562](https://github.com/MetaMask/core/pull/7562))
+- **BREAKING:** Support max amount quotes ([#7562](https://github.com/MetaMask/core/pull/7562))
+  - Add `TransactionPayController:setIsMaxAmount` messenger action.
   - Add `isMaxAmount` property to `TransactionData` type.
+  - Add `targetAmount` property to `TransactionPayQuote` and `TransactionPayTotals`.
   - Update Relay quote requests to use `EXACT_INPUT` trade type when max amount is selected.
   - Update totals calculation to account for max amount selection.
 
diff --git a/packages/transaction-pay-controller/src/strategy/bridge/bridge-quotes.test.ts b/packages/transaction-pay-controller/src/strategy/bridge/bridge-quotes.test.ts
index 920e5a57627..0eb0b433b47 100644
--- a/packages/transaction-pay-controller/src/strategy/bridge/bridge-quotes.test.ts
+++ b/packages/transaction-pay-controller/src/strategy/bridge/bridge-quotes.test.ts
@@ -716,6 +716,20 @@ describe('Bridge Quotes Utils', () => {
       });
     });
 
+    it('returns target amount in quote', async () => {
+      const quotes = await getBridgeQuotes({
+        ...request,
+        requests: [QUOTE_REQUEST_1_MOCK],
+      });
+
+      expect(quotes[0].targetAmount).toStrictEqual({
+        fiat: '24.6',
+        human: '12.3',
+        raw: QUOTE_REQUEST_1_MOCK.targetAmountMinimum,
+        usd: '36.9',
+      });
+    });
+
     it('returns target network fee in quote', async () => {
       calculateTransactionGasCostMock.mockReturnValue({
         fiat: '1.23',
diff --git a/packages/transaction-pay-controller/src/strategy/relay/relay-quotes.test.ts b/packages/transaction-pay-controller/src/strategy/relay/relay-quotes.test.ts
index 0055c331f5e..dc6dadabbc2 100644
--- a/packages/transaction-pay-controller/src/strategy/relay/relay-quotes.test.ts
+++ b/packages/transaction-pay-controller/src/strategy/relay/relay-quotes.test.ts
@@ -69,9 +69,12 @@ const QUOTE_REQUEST_MOCK: QuoteRequest = {
 const QUOTE_MOCK = {
   details: {
     currencyIn: {
+      amount: '1240000000000000000',
+      amountFormatted: '1.24',
       amountUsd: '1.24',
     },
     currencyOut: {
+      amount: '100',
       amountFormatted: '1.0',
       amountUsd: '1.23',
       currency: {
@@ -997,6 +1000,25 @@ describe('Relay Quotes Utils', () => {
       });
     });
 
+    it('includes target amount in quote', async () => {
+      successfulFetchMock.mockResolvedValue({
+        json: async () => QUOTE_MOCK,
+      } as never);
+
+      const result = await getRelayQuotes({
+        messenger,
+        requests: [QUOTE_REQUEST_MOCK],
+        transaction: TRANSACTION_META_MOCK,
+      });
+
+      expect(result[0].targetAmount).toStrictEqual({
+        human: QUOTE_MOCK.details.currencyOut.amountFormatted,
+        raw: QUOTE_MOCK.details.currencyOut.amount,
+        usd: '1.23',
+        fiat: '2.46',
+      });
+    });
+
     it('throws if fetching quote fails', async () => {
       successfulFetchMock.mockRejectedValue(new Error('Fetch error'));
 

From 46afec06e359ca38019cd43bb6ae2471ef94c24f Mon Sep 17 00:00:00 2001
From: Matthew Walsh <matthew.walsh@consensys.net>
Date: Thu, 8 Jan 2026 11:02:45 +0000
Subject: [PATCH 12/13] Add error

---
 .../src/strategy/relay/relay-quotes.test.ts   | 23 +++++++++++++++----
 .../src/strategy/relay/relay-quotes.ts        |  7 +++++-
 2 files changed, 25 insertions(+), 5 deletions(-)

diff --git a/packages/transaction-pay-controller/src/strategy/relay/relay-quotes.test.ts b/packages/transaction-pay-controller/src/strategy/relay/relay-quotes.test.ts
index dc6dadabbc2..33b9f63b6b9 100644
--- a/packages/transaction-pay-controller/src/strategy/relay/relay-quotes.test.ts
+++ b/packages/transaction-pay-controller/src/strategy/relay/relay-quotes.test.ts
@@ -252,7 +252,7 @@ describe('Relay Quotes Utils', () => {
           originChainId: 1,
           originCurrency: QUOTE_REQUEST_MOCK.sourceTokenAddress,
           recipient: QUOTE_REQUEST_MOCK.from,
-          tradeType: 'EXACT_OUTPUT',
+          tradeType: 'EXPECTED_OUTPUT',
           user: QUOTE_REQUEST_MOCK.from,
         }),
       );
@@ -281,6 +281,23 @@ describe('Relay Quotes Utils', () => {
       );
     });
 
+    it('throws if isMaxAmount is true and transaction includes data', async () => {
+      await expect(
+        getRelayQuotes({
+          messenger,
+          requests: [{ ...QUOTE_REQUEST_MOCK, isMaxAmount: true }],
+          transaction: {
+            ...TRANSACTION_META_MOCK,
+            txParams: {
+              data: '0xabc' as Hex,
+            },
+          } as TransactionMeta,
+        }),
+      ).rejects.toThrow(
+        'Max amount quotes do not support included transactions',
+      );
+    });
+
     it('includes transactions in request', async () => {
       successfulFetchMock.mockResolvedValue({
         json: async () => QUOTE_MOCK,
@@ -340,15 +357,13 @@ describe('Relay Quotes Utils', () => {
 
       expect(result[0].original.request).toStrictEqual({
         amount: QUOTE_REQUEST_MOCK.targetAmountMinimum,
-        authorizationList: expect.any(Array),
         destinationChainId: 2,
         destinationCurrency: QUOTE_REQUEST_MOCK.targetTokenAddress,
         originChainId: 1,
         originCurrency: QUOTE_REQUEST_MOCK.sourceTokenAddress,
         recipient: QUOTE_REQUEST_MOCK.from,
         slippageTolerance: '50',
-        tradeType: 'EXACT_OUTPUT',
-        txs: expect.any(Array),
+        tradeType: 'EXPECTED_OUTPUT',
         user: QUOTE_REQUEST_MOCK.from,
       });
     });
diff --git a/packages/transaction-pay-controller/src/strategy/relay/relay-quotes.ts b/packages/transaction-pay-controller/src/strategy/relay/relay-quotes.ts
index 6e6feb4cacb..4a75d1f1fb9 100644
--- a/packages/transaction-pay-controller/src/strategy/relay/relay-quotes.ts
+++ b/packages/transaction-pay-controller/src/strategy/relay/relay-quotes.ts
@@ -169,13 +169,18 @@ async function processTransactions(
     log('Updating recipient as token transfer', requestBody.recipient);
   }
 
-  const skipDelegation = isTokenTransfer || isHypercore || isMaxAmount;
+  const hasNoData = singleData === undefined || singleData === '0x';
+  const skipDelegation = hasNoData || isTokenTransfer || isHypercore;
 
   if (skipDelegation) {
     log('Skipping delegation as token transfer or Hypercore deposit');
     return;
   }
 
+  if (isMaxAmount) {
+    throw new Error('Max amount quotes do not support included transactions');
+  }
+
   const delegation = await messenger.call(
     'TransactionPayController:getDelegationTransaction',
     { transaction },

From 26359d3ad0e7ede79894924f5987acda82e511d4 Mon Sep 17 00:00:00 2001
From: Matthew Walsh <matthew.walsh@consensys.net>
Date: Thu, 8 Jan 2026 11:06:16 +0000
Subject: [PATCH 13/13] Update changelog

---
 packages/transaction-controller/CHANGELOG.md | 1 +
 1 file changed, 1 insertion(+)

diff --git a/packages/transaction-controller/CHANGELOG.md b/packages/transaction-controller/CHANGELOG.md
index 18ca9c6c0c7..01d77e04570 100644
--- a/packages/transaction-controller/CHANGELOG.md
+++ b/packages/transaction-controller/CHANGELOG.md
@@ -9,6 +9,7 @@ and this project adheres to [Semantic Versioning](https://semver.org/spec/v2.0.0
 
 ### Added
 
+- Add optional `targetFiat` property to `MetamaskPayMetadata` type ([#7562](https://github.com/MetaMask/core/pull/7562))
 - Add optional `isStateOnly` property to `TransactionMeta` and `AddTransactionOptions` ([#7591](https://github.com/MetaMask/core/pull/7591))
   - Transactions with `isStateOnly` set to `true` have no lifecycle and are not signed or published.
   - Transactions are also excluded from confirmation polling.