diff --git a/pyproject.toml b/pyproject.toml
index a50a3a8e..1024300e 100644
--- a/pyproject.toml
+++ b/pyproject.toml
@@ -72,6 +72,9 @@ sqlite-utils = "sqlite_utils.cli:cli"
 requires = ["setuptools"]
 build-backend = "setuptools.build_meta"
 
+[tool.pytest.ini_options]
+filterwarnings = ["error"]
+
 [tool.flake8]
 max-line-length = 160
 # Black compatibility, E203 whitespace before ':':