diff --git a/.github/workflows/coding-standards.yml b/.github/workflows/coding-standards.yml
index 8edb2f281f..c111159d66 100644
--- a/.github/workflows/coding-standards.yml
+++ b/.github/workflows/coding-standards.yml
@@ -146,3 +146,9 @@ jobs:
 
       - name: Ensure version-controlled files are not modified or deleted
         run: git diff --exit-code
+
+  slack-notifications:
+    name: Slack Notifications
+    uses: WordPress/wordpress-develop/.github/workflows/slack-notifications.yml@master
+    needs: [ phpcs, jshint ]
+    if: ${{ always() }}
diff --git a/.github/workflows/end-to-end-tests.yml b/.github/workflows/end-to-end-tests.yml
index 9358fc9520..e74a0f36aa 100644
--- a/.github/workflows/end-to-end-tests.yml
+++ b/.github/workflows/end-to-end-tests.yml
@@ -116,3 +116,9 @@ jobs:
 
       - name: Ensure version-controlled files are not modified or deleted
         run: git diff --exit-code
+
+  slack-notifications:
+    name: Slack Notifications
+    uses: WordPress/wordpress-develop/.github/workflows/slack-notifications.yml@master
+    needs: [ e2e-tests ]
+    if: ${{ always() }}
diff --git a/.github/workflows/javascript-tests.yml b/.github/workflows/javascript-tests.yml
index b1226bacca..8373ff66d6 100644
--- a/.github/workflows/javascript-tests.yml
+++ b/.github/workflows/javascript-tests.yml
@@ -85,3 +85,9 @@ jobs:
 
       - name: Ensure version-controlled files are not modified or deleted
         run: git diff --exit-code
+
+  slack-notifications:
+    name: Slack Notifications
+    uses: WordPress/wordpress-develop/.github/workflows/slack-notifications.yml@master
+    needs: [ test-js ]
+    if: ${{ always() }}
diff --git a/.github/workflows/php-compatibility.yml b/.github/workflows/php-compatibility.yml
index b5316fd1a6..a6b38f7ff5 100644
--- a/.github/workflows/php-compatibility.yml
+++ b/.github/workflows/php-compatibility.yml
@@ -87,3 +87,9 @@ jobs:
 
       - name: Ensure version-controlled files are not modified or deleted
         run: git diff --exit-code
+
+  slack-notifications:
+    name: Slack Notifications
+    uses: WordPress/wordpress-develop/.github/workflows/slack-notifications.yml@master
+    needs: [ php-compatibility ]
+    if: ${{ always() }}
diff --git a/.github/workflows/phpunit-tests.yml b/.github/workflows/phpunit-tests.yml
index ae6abc3ce7..936c73ce63 100644
--- a/.github/workflows/phpunit-tests.yml
+++ b/.github/workflows/phpunit-tests.yml
@@ -242,3 +242,9 @@ jobs:
         env:
           WPT_REPORT_API_KEY: "${{ secrets.WPT_REPORT_API_KEY }}"
         run: docker-compose run --rm -e WPT_REPORT_API_KEY -e WPT_PREPARE_DIR=/var/www -e WPT_TEST_DIR=/var/www php php test-runner/report.php
+
+  slack-notifications:
+    name: Slack Notifications
+    uses: WordPress/wordpress-develop/.github/workflows/slack-notifications.yml@master
+    needs: [ test-php ]
+    if: ${{ always() }}
diff --git a/.github/workflows/slack-notifications.yml b/.github/workflows/slack-notifications.yml
index 2be16eb6ef..7611f72255 100644
--- a/.github/workflows/slack-notifications.yml
+++ b/.github/workflows/slack-notifications.yml
@@ -1,26 +1,12 @@
 ##
-# Posts messages to the Making WordPress Core Slack Instance by
-# submitting data to Slack webhook URLs received by Slack Workflows.
+# A reusable workflow for posting messages to the Making WordPress
+# Core Slack Instance by submitting data to Slack webhook URLs
+# received by Slack Workflows.
 ##
 name: Slack Notifications
 
 on:
-  workflow_run:
-    workflows:
-      - Code Coverage Report
-      - Coding Standards
-      - End-to-end Tests
-      - JavaScript Tests
-      - PHP Compatibility
-      - PHPUnit Tests
-      - Test NPM
-      - Test old branches
-    types:
-      - completed
-    branches:
-      - master
-      - trunk
-      - '[3-9].[0-9]'
+  workflow_call:
 
 jobs:
   # Gathers the details needed for Slack notifications.
@@ -41,20 +27,44 @@ jobs:
       payload: ${{ steps.create-payload.outputs.payload }}
 
     steps:
-      - name: Get details about the previous workflow run
-        id: previous-result
-        uses: actions/github-script@a3e7071a34d7e1f219a8a4de9a5e0a34d1ee1293 # v4.0.2
+      - name: Get the workflow ID
+        id: current-workflow-id
+        uses: actions/github-script@441359b1a30438de65712c2fbca0abe4816fa667 # v5.0.0
         with:
           script: |
-            const workflow_runs = await github.actions.listWorkflowRuns({
-              owner: context.repo.owner,
-              repo: context.repo.repo,
-              workflow_id: ${{ github.event.workflow_run.workflow_id }},
-              branch: '${{ github.event.workflow_run.head_branch }}',
+            const workflow_run = await github.actions.getWorkflowRun({
+              owner: '${{ github.repository_owner }}',
+              repo: 'wordpress-develop',
+              run_id: ${{ github.run_id }},
+            });
+            return workflow_run.data.workflow_id;
+
+      - name: Get the workflow URL
+        id: current-workflow-url
+        uses: actions/github-script@441359b1a30438de65712c2fbca0abe4816fa667 # v5.0.0
+        with:
+          script: |
+            const workflow_run = await github.actions.getWorkflowRun({
+              owner: '${{ github.repository_owner }}',
+              repo: 'wordpress-develop',
+              run_id: ${{ github.run_id }},
+            });
+            return workflow_run.data.html_url;
+
+      - name: Get details about the previous workflow run
+        id: previous-result
+        uses: actions/github-script@441359b1a30438de65712c2fbca0abe4816fa667 # v5.0.0
+        with:
+          script: |
+            const previous_runs = await github.actions.listWorkflowRuns({
+              owner: '${{ github.repository_owner }}',
+              repo: 'wordpress-develop',
+              workflow_id: ${{ steps.current-workflow-id.outputs.result }},
+              branch: '${{ github.ref_name }}',
               per_page: 1,
               page: 2,
             });
-            return workflow_runs.data.workflow_runs[0].conclusion;
+            return previous_runs.data.workflow_runs[0].conclusion;
 
       - name: Store previous conclusion as an output
         id: previous-conclusion
@@ -64,21 +74,21 @@ jobs:
         id: commit-message
         run: |
           COMMIT_MESSAGE=$(cat <<'EOF' | awk 'NR==1' | sed 's/`/\\`/g' | sed 's/\"/\\\\"/g'
-          ${{ github.event.workflow_run.head_commit.message }}
+          ${{ github.event.head_commit.message }}
           EOF
           )
           echo "::set-output name=commit_message_escaped::${COMMIT_MESSAGE}"
 
       - name: Construct payload and store as an output
         id: create-payload
-        run: echo "::set-output name=payload::{\"workflow_name\":\"${{ github.event.workflow_run.name }}\",\"ref_name\":\"${{ github.event.workflow_run.head_branch }}\",\"run_url\":\"${{ github.event.workflow_run.html_url }}\",\"commit_message\":\"${{ steps.commit-message.outputs.commit_message_escaped }}\"}"
+        run: echo "::set-output name=payload::{\"workflow_name\":\"${{ github.workflow }}\",\"ref_name\":\"${{ github.ref_name }}\",\"run_url\":\"${{ steps.current-workflow-url.outputs.result }}\",\"commit_message\":\"${{ steps.commit-message.outputs.commit_message_escaped }}\"}"
 
   # Posts notifications when a workflow fails.
   failure:
     name: Failure notifications
     runs-on: ubuntu-latest
     needs: [ prepare ]
-    if: ${{ github.event.workflow_run.conclusion == 'failure' }}
+    if: ${{ failure() }}
 
     steps:
       - name: Post failure notifications to Slack
@@ -93,7 +103,7 @@ jobs:
     name: Fixed notifications
     runs-on: ubuntu-latest
     needs: [ prepare ]
-    if: ${{ needs.prepare.outputs.previous_conclusion == 'failure' && github.event.workflow_run.conclusion == 'success' }}
+    if: ${{ needs.prepare.outputs.previous_conclusion == 'failure' && success() }}
 
     steps:
       - name: Post failure notifications to Slack
@@ -108,7 +118,7 @@ jobs:
     name: Success notifications
     runs-on: ubuntu-latest
     needs: [ prepare ]
-    if: ${{ github.event.workflow_run.conclusion == 'success' }}
+    if: ${{ success() }}
 
     steps:
       - name: Post success notifications to Slack
@@ -123,7 +133,7 @@ jobs:
     name: Cancelled notifications
     runs-on: ubuntu-latest
     needs: [ prepare ]
-    if: ${{ github.event.workflow_run.conclusion == 'cancelled' }}
+    if: ${{ cancelled() }}
 
     steps:
       - name: Post cancelled notifications to Slack
diff --git a/.github/workflows/test-coverage.yml b/.github/workflows/test-coverage.yml
index 31f20b8bd3..a0abd2fb2a 100644
--- a/.github/workflows/test-coverage.yml
+++ b/.github/workflows/test-coverage.yml
@@ -168,3 +168,9 @@ jobs:
         with:
           file: wp-code-coverage-multisite-clover-${{ github.sha }}.xml
           flags: multisite,php
+
+  slack-notifications:
+    name: Slack Notifications
+    uses: WordPress/wordpress-develop/.github/workflows/slack-notifications.yml@master
+    needs: [ test-coverage-report ]
+    if: ${{ always() }}
diff --git a/.github/workflows/test-npm.yml b/.github/workflows/test-npm.yml
index 3774ee2851..2a121f8efb 100644
--- a/.github/workflows/test-npm.yml
+++ b/.github/workflows/test-npm.yml
@@ -154,3 +154,9 @@ jobs:
 
       - name: Ensure version-controlled files are not modified or deleted during building and cleaning
         run: git diff --exit-code
+
+  slack-notifications:
+    name: Slack Notifications
+    uses: WordPress/wordpress-develop/.github/workflows/slack-notifications.yml@master
+    needs: [ test-npm, test-npm-macos ]
+    if: ${{ always() }}
diff --git a/.github/workflows/test-old-branches.yml b/.github/workflows/test-old-branches.yml
index 2bb5664a98..86b879ad79 100644
--- a/.github/workflows/test-old-branches.yml
+++ b/.github/workflows/test-old-branches.yml
@@ -69,3 +69,9 @@ jobs:
               workflow_id: '${{ matrix.workflow }}',
               ref: '${{ matrix.branch }}'
             });
+
+  slack-notifications:
+    name: Slack Notifications
+    uses: WordPress/wordpress-develop/.github/workflows/slack-notifications.yml@master
+    needs: [ dispatch-workflows-for-old-branches ]
+    if: ${{ always() }}