diff --git a/.github/workflows/R-CMD-check-wsl.yaml b/.github/workflows/R-CMD-check-wsl.yaml
index 4a275b757..1701eac77 100644
--- a/.github/workflows/R-CMD-check-wsl.yaml
+++ b/.github/workflows/R-CMD-check-wsl.yaml
@@ -38,10 +38,10 @@ jobs:
 
       - uses: actions/checkout@v4
 
-      - uses: r-lib/actions/setup-r@v2.11.2
-      - uses: r-lib/actions/setup-pandoc@v2.11.2
+      - uses: r-lib/actions/setup-r@v2.11.3
+      - uses: r-lib/actions/setup-pandoc@v2.11.3
 
-      - uses: r-lib/actions/setup-r-dependencies@v2.11.2
+      - uses: r-lib/actions/setup-r-dependencies@v2.11.3
         with:
           extra-packages: any::rcmdcheck, local::.
 
@@ -71,7 +71,7 @@ jobs:
           sessioninfo::session_info(pkgs, include_base = TRUE)
         shell: Rscript {0}
 
-      - uses: r-lib/actions/check-r-package@v2.11.2
+      - uses: r-lib/actions/check-r-package@v2.11.3
         env:
           _R_CHECK_CRAN_INCOMING_: false
 
diff --git a/.github/workflows/R-CMD-check.yaml b/.github/workflows/R-CMD-check.yaml
index 0ae2ed63e..08fb2e0cb 100644
--- a/.github/workflows/R-CMD-check.yaml
+++ b/.github/workflows/R-CMD-check.yaml
@@ -25,7 +25,7 @@ jobs:
         config:
           - {os: macOS-latest, r: 'devel', rtools: '', opencl: true}
           - {os: macOS-latest, r: 'release', rtools: '', opencl: true}
-          - {os: windows-latest, r: 'devel', rtools: '44'}
+          - {os: windows-latest, r: 'devel', rtools: '45'}
           - {os: windows-latest, r: 'release', rtools: '44'}
           - {os: windows-latest, r: 'oldrel', rtools: '43'}
           - {os: ubuntu-latest, r: 'devel', rtools: '', opencl: true}
@@ -50,14 +50,14 @@ jobs:
 
       - uses: actions/checkout@v4
 
-      - uses: r-lib/actions/setup-r@v2.11.2
+      - uses: r-lib/actions/setup-r@v2.11.3
         with:
           r-version: ${{ matrix.config.r }}
           rtools-version: ${{ matrix.config.rtools }}
 
-      - uses: r-lib/actions/setup-pandoc@v2.11.2
+      - uses: r-lib/actions/setup-pandoc@v2.11.3
 
-      - uses: r-lib/actions/setup-r-dependencies@v2.11.2
+      - uses: r-lib/actions/setup-r-dependencies@v2.11.3
         with:
           cache: "always"
           extra-packages: any::rcmdcheck, local::.
@@ -90,7 +90,7 @@ jobs:
           sessioninfo::session_info(pkgs, include_base = TRUE)
         shell: Rscript {0}
 
-      - uses: r-lib/actions/check-r-package@v2.11.2
+      - uses: r-lib/actions/check-r-package@v2.11.3
         env:
           _R_CHECK_CRAN_INCOMING_: false
 
diff --git a/.github/workflows/Test-coverage.yaml b/.github/workflows/Test-coverage.yaml
index 9d93c41d2..4e9641531 100644
--- a/.github/workflows/Test-coverage.yaml
+++ b/.github/workflows/Test-coverage.yaml
@@ -42,10 +42,10 @@ jobs:
         if: "!startsWith(github.ref, 'refs/tags/') && github.ref != 'refs/heads/master'"
       - uses: actions/checkout@v4
 
-      - uses: r-lib/actions/setup-r@v2.11.2
-      - uses: r-lib/actions/setup-pandoc@v2.11.2
+      - uses: r-lib/actions/setup-r@v2.11.3
+      - uses: r-lib/actions/setup-pandoc@v2.11.3
 
-      - uses: r-lib/actions/setup-r-dependencies@v2.11.2
+      - uses: r-lib/actions/setup-r-dependencies@v2.11.3
         with:
           extra-packages: any::rcmdcheck, local::., any::covr, any::gridExtra
 
diff --git a/.github/workflows/cmdstan-tarball-check.yaml b/.github/workflows/cmdstan-tarball-check.yaml
index 362580c82..ec2c91b58 100644
--- a/.github/workflows/cmdstan-tarball-check.yaml
+++ b/.github/workflows/cmdstan-tarball-check.yaml
@@ -40,12 +40,12 @@ jobs:
           sudo apt-get install -y libcurl4-openssl-dev || true
           sudo apt-get install -y openmpi-bin openmpi-common libopenmpi-dev || true
 
-      - uses: r-lib/actions/setup-r@v2.11.2
+      - uses: r-lib/actions/setup-r@v2.11.3
         with:
           r-version: ${{ matrix.config.r }}
           rtools-version: ${{ matrix.config.rtools }}
 
-      - uses: r-lib/actions/setup-pandoc@v2.11.2
+      - uses: r-lib/actions/setup-pandoc@v2.11.3
 
       - name: Query dependencies
         run: |
diff --git a/R/install.R b/R/install.R
index 0ddf6e02e..a75ff5cbe 100644
--- a/R/install.R
+++ b/R/install.R
@@ -895,8 +895,10 @@ rtools4x_version <- function() {
     rtools_ver <- "42"
   } else if (R.version$minor < "4.0") {
     rtools_ver <- "43"
-  } else {
+  } else if (R.version$minor < "5.0") {
     rtools_ver <- "44"
+  } else {
+    rtools_ver <- "45"
   }
   rtools_ver
 }