1 files changed, 2 insertions, 2 deletions

diff --git a/tox.ini b/tox.ini

index ab6557f15e..1c042cb227 100644
--- a/tox.ini
+++ b/tox.ini
@@ -131,8 +131,8 @@ commands =
 
 [testenv:check_isort]
 skip_install = True
-deps = isort
-commands = /bin/sh -c "isort -c -df -sp setup.cfg -rc synapse tests scripts-dev scripts"
+deps = isort==5.0.3
+commands = /bin/sh -c "isort -c --df --sp setup.cfg synapse tests scripts-dev scripts"
 
 [testenv:check-newsfragment]
 skip_install = True