diff --git a/.github/workflows/release-readiness.yml b/.github/workflows/release-readiness.yml
index 96c0bf1b94a..30bbafc49bc 100644
--- a/.github/workflows/release-readiness.yml
+++ b/.github/workflows/release-readiness.yml
@@ -1,7 +1,7 @@
 name: Release readiness (snapshot dependency)
-
-# Makes sure that we aren't relying on SNAPSHOT/dev versions of smithy-kotlin before merging
-# Otherwise we could forget because the rest of CI is masking it
+description: >
+  Makes sure that we aren't relying on SNAPSHOT/dev versions of smithy-kotlin before merging
+  otherwise we could forget because the rest of CI is masking it.
 
 on:
   pull_request:
@@ -11,22 +11,57 @@ jobs:
   release-readiness:
     runs-on: ubuntu-latest
     steps:
-      - name: Checkout sources
+      - name: Checkout SDK
         uses: actions/checkout@v4
+        with:
+          path: 'aws-sdk-kotlin'
 
       - name: Configure Gradle
         uses: awslabs/aws-kotlin-repo-tools/.github/actions/configure-gradle@main
+        with:
+          working-directory: ./aws-sdk-kotlin
 
       - name: Build SDK
+        working-directory: ./aws-sdk-kotlin
         run: ./gradlew test jvmTest
 
       - name: Build SDK client
+        working-directory: ./aws-sdk-kotlin
         run: |
           ./gradlew -Paws.kotlin.native=false -Paws.services=s3 bootstrap
           ./gradlew -Paws.kotlin.native=false build
 
+      - name: Checkout smithy-kotlin
+        uses: awslabs/aws-kotlin-repo-tools/.github/actions/checkout-head@main
+        with:
+          path: 'smithy-kotlin'
+          repository: 'smithy-lang/smithy-kotlin'
+
+      - name: Check for smithy-kotlin unreleased changes
+        run: |
+          echo "aws-sdk-kotlin branch: $GITHUB_HEAD_REF"
+          
+          cd smithy-kotlin
+          SMITHY_KOTLIN_BRANCH=$(git branch --show-current)
+          echo "smithy-kotlin branch: $SMITHY_KOTLIN_BRANCH"
+          
+          if [ "$GITHUB_HEAD_REF" == "$SMITHY_KOTLIN_BRANCH" ]; then
+            cd ../aws-sdk-kotlin
+            git fetch origin
+
+            DIFF=$(git diff origin/main -- gradle/libs.versions.toml | grep '^[-+][^-+]'; exit 0)
+            SMITHY_KOTLIN_VERSION_BUMP=$(echo "$DIFF" | grep "smithy-kotlin-runtime-version =\|smithy-kotlin-codegen-version ="; exit 0)
+
+            if [ -z "$SMITHY_KOTLIN_VERSION_BUMP" ]; then
+              echo "::error::Matching smithy-kotlin and aws-sdk-kotlin branches but no smithy-kotlin version bump"
+              exit 1
+            else
+              echo "Matching smithy-kotlin and aws-sdk-kotlin branches with smithy-kotlin version bump detected"
+            fi
+          fi
+
       - name: Emit error message
         if: ${{ failure() }}
         run: |
-          echo "::error ::Build failed. Did you forget to release smithy-kotlin and bump the dependency version?"
+          echo "::error::Did you forget to release smithy-kotlin and bump the dependency version?"
           exit 1