diff --git a/.github/workflows/check-go-versions.yml b/.github/workflows/check-go-versions.yml
index c6e26bf1..debe4b20 100644
--- a/.github/workflows/check-go-versions.yml
+++ b/.github/workflows/check-go-versions.yml
@@ -51,21 +51,33 @@ jobs:
         id: go-versions
         run:  cat ./.github/variables/go-versions.env > $GITHUB_OUTPUT
 
-      - name: Update go-versions.env
+      - name: Update go-versions.env and README.md
         if: steps.go-versions.outputs.latest != env.officialLatestVersion
-        id: update
+        id: update-go-versions
         run: |
-          sed < ./.github/variables/go-versions.env > updated-versions.tmp
-            -e "s#latest=[^ ]*#latest=${{ env.officialLatestVersion }}#g"
-            -e "s#penultimate=[^ ]*#penultimate=${{ env.officialPenultimateVersion }}#g"
-          mv updated-versions.tmp ./.github/variables/go-versions.env
+          sed -e "s#latest=[^ ]*#latest=${{ env.officialLatestVersion }}#g"
+              -e "s#penultimate=[^ ]*#penultimate=${{ env.officialPenultimateVersion }}#g"
+              ./.github/variables/go-versions.env
+          sed -i "s/Go version {{ steps.go-versions.outputs.penultimate }}/Go version ${{ env.officialPenultimateVersion }}/g" README.md
+
+      - name: Update go.mod and testservice/go.mod
+        if: steps.update-go-versions.outcome == 'success'
+        id: update-go-mod
+        run: |
+          go mod edit -go=${{ env.officialPenultimateVersion }}
+          cd testservice
+          go mod edit -go=${{ env.officialPenultimateVersion }}
 
       - name: Create pull request
-        if: steps.update.outcome == 'success'
+        if: steps.update-go-mod.outcome == 'success'
         uses: peter-evans/create-pull-request@v6
         with:
           token: ${{ secrets.GITHUB_TOKEN }}
-          add-paths: .github/variables/go-versions.env
+          add-paths: |
+            .github/variables/go-versions.env
+            README.md
+            go.mod
+            testservice/go.mod
           branch: "launchdarklyreleasebot/update-to-go${{ env.officialLatestVersion }}-${{ matrix.branch }}"
           author: "LaunchDarklyReleaseBot <LaunchDarklyReleaseBot@launchdarkly.com>"
           committer: "LaunchDarklyReleaseBot <LaunchDarklyReleaseBot@launchdarkly.com>"