diff --git a/noxfile.py b/noxfile.py
index 2cefbf00..19b773fa 100644
--- a/noxfile.py
+++ b/noxfile.py
@@ -18,7 +18,7 @@
 
 
 #: Default to reusing any pre-existing nox environments.
-nox.options.reuse_existing_virtualenvs = True
+nox.options.reuse_existing_virtualenvs = False
 
 #: Name of the package to test.
 PACKAGE = "esmf_regrid"