diff --git a/src/features/tags/components/TagManager/components/TagDialog/index.tsx b/src/features/tags/components/TagManager/components/TagDialog/index.tsx
index 0915de143..55b9f6c63 100644
--- a/src/features/tags/components/TagManager/components/TagDialog/index.tsx
+++ b/src/features/tags/components/TagManager/components/TagDialog/index.tsx
@@ -81,7 +81,7 @@ const TagDialog: React.FunctionComponent<TagDialogProps> = ({
           e.preventDefault();
           e.stopPropagation();
           const tagBody = {
-            ...(color.value && { color: `#${color.value}` }),
+            ...(color.value && { color: `#${color.value}`.toLowerCase() }),
             ...(tag && 'id' in tag && { id: tag.id }),
             ...(type && { value_type: type }),
             title,