diff --git a/dev-requirements.txt b/dev-requirements.txt
index 2c0a449..ce316a0 100644
--- a/dev-requirements.txt
+++ b/dev-requirements.txt
@@ -2,5 +2,5 @@ pylint>=1.6,<3
 pytest>=3.0,<7
 coverage>=4.3,<7
 setuptools_scm>=1.15,<7.0
-tox>=2.5,<4.0
+tox>=2.5,<5.0
 pytest-cov>=2.5,<4.0
\ No newline at end of file