diff --git a/tox.ini b/tox.ini
index 59aa4a0cd7..baef6d1423 100644
--- a/tox.ini
+++ b/tox.ini
@@ -16,6 +16,10 @@ commands =
     py27: python -m compileall -fq -x 'test/samples' lib test contrib
     py3{5,6}: python -m compileall -fq -x 'test/samples|lib/ansible/modules' lib test contrib
     make tests
+passenv =
+    # Pass HOME to the test environment to avoid the missing HOME env
+    # variable error. See issue: #20424
+    HOME
 
 
 [flake8]