diff --git a/tests/unit_tests/test_filters.py b/tests/unit_tests/test_filters.py
index 4e741e60f9..a20b129e91 100644
--- a/tests/unit_tests/test_filters.py
+++ b/tests/unit_tests/test_filters.py
@@ -1,4 +1,3 @@
-import math
 import numpy as np
 import openmc
 from pytest import fixture, approx