diff --git a/tox.ini b/tox.ini
index 3f4728fdedb7..e8b1901abbbc 100644
--- a/tox.ini
+++ b/tox.ini
@@ -55,15 +55,18 @@ deps =
     pylint
     unittest2
     protobuf==3.0.0-alpha-1
+passenv = {[testenv:regression]passenv}
 
 [testenv:regression]
 basepython =
     python2.7
 commands =
     {toxinidir}/scripts/run_regression.sh
+passenv = GOOGLE_* GCLOUD_* TRAVIS* encrypted_*
 
 [testenv:regression3]
 basepython =
     python3.4
 commands =
     {toxinidir}/scripts/run_regression.sh
+passenv = {[testenv:regression]passenv}