diff --git a/tox.ini b/tox.ini
index 67bd00698..d0de3ed0e 100644
--- a/tox.ini
+++ b/tox.ini
@@ -40,7 +40,7 @@ install_packages =
     python {toxinidir}/tools/pip_install_editable.py {[base]all_packages}
 source_paths =
     acme/acme
-    certbot
+    certbot/certbot
     certbot-apache/certbot_apache
     certbot-compatibility-test/certbot_compatibility_test
     certbot-dns-cloudflare/certbot_dns_cloudflare