diff --git a/.github/workflows/main.yml b/.github/workflows/main.yml
index bd7fc96..b35db6f 100644
--- a/.github/workflows/main.yml
+++ b/.github/workflows/main.yml
@@ -25,7 +25,7 @@ jobs:
           submodules: recursive
 
       - name: Set up Julia
-        uses: julia-actions/install-juliaup@v3
+        uses: julia-actions/install-juliaup@v3.1.4
         with:
           channel: "lts"
 
@@ -221,7 +221,7 @@ jobs:
           key: ${{ hashFiles('**/*.stan', 'src/*', 'stan/src/stan/version.hpp', 'Makefile') }}-${{ matrix.os }}-v${{ env.CACHE_VERSION }}
 
       - name: Set up Julia
-        uses: julia-actions/install-juliaup@v3
+        uses: julia-actions/install-juliaup@v3.1.4
         with:
           channel: ${{ matrix.julia-version }}