diff --git a/.github/workflows/build.yml b/.github/workflows/build.yml
index 3f118c2b..c4184a8d 100644
--- a/.github/workflows/build.yml
+++ b/.github/workflows/build.yml
@@ -136,6 +136,7 @@ jobs:
       is-release: ${{ steps.determination.outputs.is-release }}
       is-nightly: ${{ steps.determination.outputs.is-nightly }}
       channel-name: ${{ steps.determination.outputs.channel-name }}
+      publish-to-s3: ${{ steps.determination.outputs.publish-to-s3 }}
     permissions: {}
     steps:
       - name: Determine the type of build
@@ -166,6 +167,8 @@ jobs:
           echo "is-release=$is_release" >> $GITHUB_OUTPUT
           echo "is-nightly=$is_nightly" >> $GITHUB_OUTPUT
           echo "channel-name=$channel_name" >> $GITHUB_OUTPUT
+          # Only attempt upload to Amazon S3 if the credentials are available.
+          echo "publish-to-s3=${{ github.repository == 'arduino/arduino-ide' }}" >> $GITHUB_OUTPUT
 
   select-targets:
     needs: build-type-determination
@@ -509,7 +512,7 @@ jobs:
       - merge-channel-files-complete
       - changelog
     if: >
-      github.repository == 'arduino/arduino-ide' &&
+      needs.build-type-determination.outputs.publish-to-s3 == 'true' &&
       needs.build-type-determination.outputs.is-nightly == 'true'
     runs-on: ubuntu-latest
     steps:
@@ -566,7 +569,7 @@ jobs:
           rm "${{ env.JOB_TRANSFER_ARTIFACT }}/stable-linux.yml"
 
       - name: Publish Release [S3]
-        if: github.repository == 'arduino/arduino-ide'
+        if: needs.build-type-determination.outputs.publish-to-s3 == 'true'
         uses: docker://plugins/s3
         env:
           PLUGIN_SOURCE: '${{ env.JOB_TRANSFER_ARTIFACT }}/*'