diff --git a/tox.ini b/tox.ini
index 00eea4f3b..9417aef7d 100644
--- a/tox.ini
+++ b/tox.ini
@@ -26,7 +26,7 @@ minversion = 4
 # Install code the real way, for maximum realism.
 usedevelop = False
 
-passenv = TAHOE_LAFS_*,PIP_*,SUBUNITREPORTER_*,USERPROFILE,HOMEDRIVE,HOMEPATH
+passenv = TAHOE_LAFS_*,PIP_*,SUBUNITREPORTER_*,USERPROFILE,HOMEDRIVE,HOMEPATH,COLUMNS
 deps =
     # We pull in certify *here* to avoid bug #2913. Basically if a
     # `setup_requires=...` causes a package to be installed (with setuptools)
@@ -141,7 +141,7 @@ commands = mypy src
 
 
 [testenv:draftnews]
-passenv = TAHOE_LAFS_*,PIP_*,SUBUNITREPORTER_*,USERPROFILE,HOMEDRIVE,HOMEPATH
+passenv = TAHOE_LAFS_*,PIP_*,SUBUNITREPORTER_*,USERPROFILE,HOMEDRIVE,HOMEPATH,COLUMNS
 deps =
     # see comment in [testenv] about "certifi"
     certifi
@@ -151,7 +151,7 @@ commands =
 
 [testenv:news]
 # On macOS, git invoked from Tox needs $HOME.
-passenv = TAHOE_LAFS_*,PIP_*,SUBUNITREPORTER_*,USERPROFILE,HOMEDRIVE,HOMEPATH
+passenv = TAHOE_LAFS_*,PIP_*,SUBUNITREPORTER_*,USERPROFILE,HOMEDRIVE,HOMEPATH,COLUMNS
 whitelist_externals =
     git
 deps =