diff --git a/tox.ini b/tox.ini
index dcde59065f..b93be53014 100644
--- a/tox.ini
+++ b/tox.ini
@@ -11,7 +11,7 @@ commands = make check-dictionaries
 [testenv:unitest]
 description = run unit tests
 dependency_groups = dev
-commands = pytest --cov=codespell_lib codespell_lib
+commands = pytest --cov=codespell_lib {posargs} codespell_lib
 
 [testenv:type]
 description = run type checks