diff --git a/.github/workflows/biweekly-time-reporting.yml b/.github/workflows/biweekly-time-reporting.yml
index 9fddc0c..a3052c5 100644
--- a/.github/workflows/biweekly-time-reporting.yml
+++ b/.github/workflows/biweekly-time-reporting.yml
@@ -90,7 +90,7 @@ jobs:
       - name: Post to Slack
         id: slack
         if: success()
-        uses: slackapi/slack-github-action@v3.0.3
+        uses: slackapi/slack-github-action@v4.0.0
         with:
           method: files.uploadV2
           token: ${{ secrets.SLACK_BOT_TOKEN }}
diff --git a/.github/workflows/monthly-time-reporting.yml b/.github/workflows/monthly-time-reporting.yml
index 725f9fd..5b4b81b 100644
--- a/.github/workflows/monthly-time-reporting.yml
+++ b/.github/workflows/monthly-time-reporting.yml
@@ -136,7 +136,7 @@ jobs:
       - name: Post to Slack
         id: slack
         if: success()
-        uses: slackapi/slack-github-action@v3.0.3
+        uses: slackapi/slack-github-action@v4.0.0
         with:
           method: files.uploadV2
           token: ${{ secrets.SLACK_BOT_TOKEN }}