diff --git a/tox.ini b/tox.ini
index 1a386744..a849cd95 100644
--- a/tox.ini
+++ b/tox.ini
@@ -58,9 +58,9 @@ commands =
 
 [testenv:flake8]
 deps =
-    flake8==3.5.0
-    flake8-docstrings==1.3.0
-    flake8-import-order==0.16
+    flake8==3.7.8
+    flake8-docstrings==1.5.0
+    flake8-import-order==0.18.1
 skip_install = true
 commands =
     flake8 prometheus_client/ tests/ setup.py