diff --git a/.github/workflows/test.yml b/.github/workflows/test.yml
index dd90881a..4a6cc09f 100644
--- a/.github/workflows/test.yml
+++ b/.github/workflows/test.yml
@@ -81,7 +81,7 @@ jobs:
         python -m pip install --upgrade pip tox>=3.5
     - name: Test with tox
       env:
-        TOX_ENV: ${{ format('py{0}-django{1}-cms{2}', matrix.python-version, matrix.django, matrix.cms) }}
+        TOX_ENV: ${{ format('py-django{1}-cms{2}', matrix.python-version, matrix.django, matrix.cms) }}
         COMMAND: coverage run
         COVERALLS_REPO_TOKEN: ${{ secrets.GITHUB_TOKEN }}
         COVERALLS_SERVICE_NAME: github
diff --git a/changes/606.bugfix b/changes/606.bugfix
new file mode 100644
index 00000000..c9554939
--- /dev/null
+++ b/changes/606.bugfix
@@ -0,0 +1 @@
+Fix python version declaration in tox
diff --git a/tox.ini b/tox.ini
index 4aeaf04f..5e0a80a0 100644
--- a/tox.ini
+++ b/tox.ini
@@ -8,8 +8,8 @@ envlist =
     pep8
     pypi-description
     towncrier
-    py{3.8,3.7,3.6}-django{30}-cms{37,no-search-37}
-    py{3.8,3.7,3.6,3.5}-django{22}-cms{37,no-search-37}
+    py{38,37,36}-django{30}-cms{37,no-search-37}
+    py{38,37,36,35}-django{22}-cms{37,no-search-37}
 
 [testenv]
 commands = {env:COMMAND:python} cms_helper.py djangocms_blog test {posargs}