diff --git a/tox.ini b/tox.ini
index fc6d9959..c9b8fea4 100644
--- a/tox.ini
+++ b/tox.ini
@@ -28,7 +28,7 @@ deps =
     devdeps: git+https://github.com/sunpy/sunpy.git
     devdeps: numpy>=0.0.dev0
     oldestdeps: sunpy<6.0
-    oldestdeps: scikit-image<0.24.0 ### KNOW THAT 0.24.0 works and is the latest
+    oldestdeps: scikit-image<0.21.0 ### KNOW THAT 0.24.0 works and is the latest
     oldestdeps: scipy<1.19.0
     oldestdeps: numpy<2.00.0
     figure-!devdeps: astropy==6.1.0