diff --git a/.github/workflows/cleanup-cache.yml b/.github/workflows/cleanup-cache.yml
new file mode 100644
index 0000000..573d406
--- /dev/null
+++ b/.github/workflows/cleanup-cache.yml
@@ -0,0 +1,45 @@
+name: Cleanup S3 Cache
+
+on:
+  workflow_dispatch:
+    inputs:
+      branch:
+        description: "Branch name to clean cache for (e.g., 'feature/my-branch')"
+        required: true
+        type: string
+      key:
+        description: "Cache key prefix to delete (e.g., 'sccache-Linux-'). Leave empty to delete all cache for the branch."
+        required: false
+        type: string
+        default: ""
+      environment:
+        description: "Target environment"
+        required: false
+        type: choice
+        options:
+          - prod
+          - dev
+        default: prod
+      dry-run:
+        description: "Preview mode - show what would be deleted without deleting"
+        required: false
+        type: boolean
+        default: true
+
+jobs:
+  cleanup:
+    runs-on: github-ubuntu-latest-s
+    permissions:
+      id-token: write
+      contents: read
+    steps:
+      - name: Checkout
+        uses: actions/checkout@11bd71901bbe5b1630ceea73d27597364c9af683 # v4.2.2
+
+      - name: Cleanup cache
+        uses: ./cleanup
+        with:
+          branch: ${{ inputs.branch }}
+          key: ${{ inputs.key }}
+          environment: ${{ inputs.environment }}
+          dry-run: ${{ inputs.dry-run }}
diff --git a/.github/workflows/test-action.yml b/.github/workflows/test-action.yml
index 682bfd4..fe15c93 100644
--- a/.github/workflows/test-action.yml
+++ b/.github/workflows/test-action.yml
@@ -328,3 +328,18 @@ jobs:
           pip install pytest requests
 
       # SUCCESS: credential-guard post step runs, then runs-on/cache saves to S3
+
+  test-cleanup-dry-run:
+    runs-on: github-ubuntu-latest-s
+    permissions:
+      id-token: write
+      contents: read
+    steps:
+      - uses: actions/checkout@11bd71901bbe5b1630ceea73d27597364c9af683 # v4.2.2
+
+      - name: Dry-run cleanup against real S3
+        uses: ./cleanup
+        with:
+          branch: test-cleanup-nonexistent
+          environment: dev
+          dry-run: "true"
diff --git a/README.md b/README.md
index 65fa005..41af5e3 100644
--- a/README.md
+++ b/README.md
@@ -212,3 +212,59 @@ jobs:
 
 The AWS S3 bucket lifecycle rules apply to delete the old files. The content from default branches expires in 60 days and for feature
 branches in 30 days.
+
+## Cache Cleanup
+
+Delete S3 cache entries for a specific branch and/or cache key prefix without waiting for the 30-day lifecycle expiry.
+
+### Setup
+
+Add a cleanup workflow to your repository:
+
+```yaml
+# .github/workflows/cleanup-cache.yml
+name: Cleanup S3 Cache
+
+on:
+  workflow_dispatch:
+    inputs:
+      branch:
+        description: "Branch name (e.g., 'feature/my-branch')"
+        required: true
+        type: string
+      key:
+        description: "Cache key prefix (optional). Leave empty to delete all cache for the branch."
+        required: false
+        type: string
+        default: ""
+      dry-run:
+        description: "Preview deletions without executing them"
+        required: false
+        type: boolean
+        default: false
+
+jobs:
+  cleanup:
+    runs-on: github-ubuntu-latest-s
+    permissions:
+      id-token: write
+      contents: read
+    steps:
+      - uses: SonarSource/gh-action_cache/cleanup@v1
+        with:
+          branch: ${{ inputs.branch }}
+          key: ${{ inputs.key }}
+          dry-run: ${{ inputs.dry-run }}
+```
+
+> **Important:** The workflow must be dispatched from a **default/protected branch** (e.g., `main` or `master`).
+> This is required by the IAM policy for cross-branch cache deletion.
+
+### Running Cleanup
+
+**Via GitHub Actions UI:**
+
+1. Go to **Actions** > **Cleanup S3 Cache** > **Run workflow**
+2. Enter the branch name as you know it (e.g., `feature/my-branch` or `master`)
+3. Optionally enter a cache key prefix (e.g., `sccache-Linux-`)
+4. Optionally enable **dry-run** to preview what would be deleted
diff --git a/cleanup/action.yml b/cleanup/action.yml
new file mode 100644
index 0000000..bc50c32
--- /dev/null
+++ b/cleanup/action.yml
@@ -0,0 +1,54 @@
+name: S3 Cache Cleanup
+description: Delete S3 cache entries by branch name and optional key prefix
+author: SonarSource
+
+inputs:
+  branch:
+    description: >
+      Branch name to clean cache for.
+      Examples: "master", "feature/my-branch".
+      Automatically finds cache entries regardless of how they were created (PR or push).
+    required: true
+  key:
+    description: >
+      Cache key prefix to delete (optional). If empty, deletes ALL cache entries for the branch.
+      Examples: "sccache-Linux-", "orchestrator-2026-"
+    required: false
+    default: ""
+  environment:
+    description: Environment to use ('dev' or 'prod')
+    required: false
+    default: prod
+  dry-run:
+    description: Preview deletions without executing them
+    required: false
+    default: "false"
+
+runs:
+  using: composite
+  steps:
+    - name: Set action path
+      shell: bash
+      run: |
+        echo "ACTION_PATH_CLEANUP=${{ github.action_path }}" >> "$GITHUB_ENV"
+
+    - name: Setup S3 cache credentials
+      id: aws-auth
+      uses: SonarSource/gh-action_cache/credential-setup@v1
+      with:
+        environment: ${{ inputs.environment }}
+
+    - name: Run cache cleanup
+      shell: bash
+      env:
+        CLEANUP_BRANCH: ${{ inputs.branch }}
+        CLEANUP_KEY: ${{ inputs.key }}
+        S3_BUCKET: sonarsource-s3-cache-${{ inputs.environment }}-bucket
+        GITHUB_REPOSITORY: ${{ github.repository }}
+        DRY_RUN: ${{ inputs.dry-run }}
+        AWS_ACCESS_KEY_ID: ${{ steps.aws-auth.outputs.AWS_ACCESS_KEY_ID }}
+        AWS_SECRET_ACCESS_KEY: ${{ steps.aws-auth.outputs.AWS_SECRET_ACCESS_KEY }}
+        AWS_SESSION_TOKEN: ${{ steps.aws-auth.outputs.AWS_SESSION_TOKEN }}
+        AWS_DEFAULT_REGION: eu-central-1
+        AWS_REGION: eu-central-1
+      run: "$ACTION_PATH_CLEANUP/../scripts/cleanup-cache.sh"
diff --git a/scripts/cleanup-cache.sh b/scripts/cleanup-cache.sh
new file mode 100755
index 0000000..741111e
--- /dev/null
+++ b/scripts/cleanup-cache.sh
@@ -0,0 +1,78 @@
+#!/bin/bash
+set -euo pipefail
+
+# Self-service S3 cache cleanup script.
+# Deletes cache objects matching a branch and optional key pattern.
+#
+# The branch name in S3 varies by event type:
+#   - PR events use GITHUB_HEAD_REF (bare name, e.g., "feat/my-branch")
+#   - Push events use GITHUB_REF (full ref, e.g., "refs/heads/master")
+# This script searches for BOTH forms to cover all cached objects.
+#
+# Required environment variables:
+#   - CLEANUP_BRANCH: Branch name (e.g., "feature/my-branch" or "refs/heads/feature/my-branch")
+#   - S3_BUCKET: S3 bucket name (e.g., "sonarsource-s3-cache-prod-bucket")
+#   - GITHUB_REPOSITORY: Repository in org/repo format
+#
+# Optional environment variables:
+#   - CLEANUP_KEY: Cache key prefix to match (e.g., "sccache-Linux-"). If empty, deletes all cache for the branch.
+#   - DRY_RUN: Set to "true" to preview deletions without executing them.
+
+: "${CLEANUP_BRANCH:?}" "${S3_BUCKET:?}" "${GITHUB_REPOSITORY:?}"
+
+# Derive both bare and full ref forms of the branch name
+INPUT_BRANCH="${CLEANUP_BRANCH}"
+if [[ "$INPUT_BRANCH" == refs/heads/* ]]; then
+  BARE_BRANCH="${INPUT_BRANCH#refs/heads/}"
+  FULL_REF_BRANCH="$INPUT_BRANCH"
+elif [[ "$INPUT_BRANCH" == refs/pull/* ]]; then
+  # PR ref - use as-is, no bare form
+  BARE_BRANCH="$INPUT_BRANCH"
+  FULL_REF_BRANCH="$INPUT_BRANCH"
+else
+  BARE_BRANCH="$INPUT_BRANCH"
+  FULL_REF_BRANCH="refs/heads/${INPUT_BRANCH}"
+fi
+
+S3_PREFIX="s3://${S3_BUCKET}/cache/${GITHUB_REPOSITORY}/"
+KEY_PATTERN="${CLEANUP_KEY:-}"
+
+# Build include patterns for both bare (PR) and full ref (push) forms
+if [[ -n "$KEY_PATTERN" ]]; then
+  INCLUDE_BARE="*/${BARE_BRANCH}/${KEY_PATTERN}*"
+  INCLUDE_FULL="*/${FULL_REF_BRANCH}/${KEY_PATTERN}*"
+  echo "Deleting cache entries matching branch='${BARE_BRANCH}' key='${KEY_PATTERN}*'"
+else
+  INCLUDE_BARE="*/${BARE_BRANCH}/*"
+  INCLUDE_FULL="*/${FULL_REF_BRANCH}/*"
+  echo "Deleting ALL cache entries for branch='${BARE_BRANCH}'"
+fi
+
+echo "Repository: ${GITHUB_REPOSITORY}"
+echo "Bucket: ${S3_BUCKET}"
+
+CMD=(aws s3 rm "${S3_PREFIX}" --recursive --exclude "*" --include "${INCLUDE_BARE}" --include "${INCLUDE_FULL}")
+if [[ "${DRY_RUN:-false}" == "true" ]]; then
+  CMD+=(--dryrun)
+  echo ""
+  echo "=== DRY RUN MODE - no objects will be deleted ==="
+  echo ""
+fi
+
+EXIT_CODE=0
+OUTPUT=$("${CMD[@]}" 2>&1) || EXIT_CODE=$?
+echo "$OUTPUT"
+
+if [[ $EXIT_CODE -ne 0 ]]; then
+  echo "" >&2
+  echo "ERROR: aws s3 rm failed with exit code ${EXIT_CODE}" >&2
+  exit $EXIT_CODE
+fi
+
+if [[ -z "$OUTPUT" ]]; then
+  echo "No matching cache entries found."
+else
+  MATCH_COUNT=$(echo "$OUTPUT" | grep -c "delete:" || true)
+  echo ""
+  echo "Cache cleanup completed. ${MATCH_COUNT} object(s) matched."
+fi