diff --git a/src/calibre/utils/img.py b/src/calibre/utils/img.py
index 3278fbc1e6..1a6797d442 100644
--- a/src/calibre/utils/img.py
+++ b/src/calibre/utils/img.py
@@ -326,7 +326,7 @@ def resize_to_fit(img, width, height):
     img = image_from_data(img)
     resize_needed, nw, nh = fit_image(img.width(), img.height(), width, height)
     if resize_needed:
-        resize_image(img, nw, nh)
+        img = resize_image(img, nw, nh)
     return resize_needed, img