diff --git a/.github/workflows/pytest.yaml b/.github/workflows/pytest.yaml
index fa0c35fb..6bcff0e0 100644
--- a/.github/workflows/pytest.yaml
+++ b/.github/workflows/pytest.yaml
@@ -56,7 +56,7 @@ jobs:
       - name: Run pytest
         run: pytest pycrostates --cov=pycrostates --cov-report=xml --cov-config=pyproject.toml
       - name: Upload to codecov
-        uses: codecov/codecov-action@v3
+        uses: codecov/codecov-action@v4
         with:
           files: ./coverage.xml
           flags: unittests  # optional
@@ -111,7 +111,7 @@ jobs:
       - name: Run pytest
         run: pytest pycrostates --cov=pycrostates --cov-report=xml --cov-config=pyproject.toml
       - name: Upload to codecov
-        uses: codecov/codecov-action@v3
+        uses: codecov/codecov-action@v4
         with:
           files: ./coverage.xml
           flags: unittests  # optional