diff --git a/tests/snapshot_tests/conftest.py b/tests/snapshot_tests/conftest.py
index 92871e0bc..76cf997a0 100644
--- a/tests/snapshot_tests/conftest.py
+++ b/tests/snapshot_tests/conftest.py
@@ -120,7 +120,7 @@ def pytest_sessionfinish(
             num_snapshot_tests=num_snapshot_tests,
             now=datetime.utcnow(),
         )
-        with open(snapshot_report_path, "wt") as snapshot_file:
+        with open(snapshot_report_path, "w+") as snapshot_file:
             snapshot_file.write(rendered_report)
 
         session.config._textual_snapshots = diffs