diff --git a/apps/sumo/tests/test_googleanalytics.py b/apps/sumo/tests/test_googleanalytics.py
index 75398dd56..6f06c4c16 100644
--- a/apps/sumo/tests/test_googleanalytics.py
+++ b/apps/sumo/tests/test_googleanalytics.py
@@ -166,8 +166,8 @@ VISITORS_BY_LOCALE_RESPONSE = {
         [u'/sl/', u'530'],
         [u'/son/', u'1'],
         [u'/sq/', u'27'],
-        [u'/sr-CYRL/', u'256'],
-        [u'/sr-LATN/', u'31'],
+        [u'/sr-Cyrl/', u'256'],
+        [u'/sr-Latn/', u'31'],
         [u'/sv/', u'1488'],
         [u'/ta-LK/', u'13'],
         [u'/ta/', u'13'],
diff --git a/lib/languages.json b/lib/languages.json
index e8dc01777..c320adfbe 100644
--- a/lib/languages.json
+++ b/lib/languages.json
@@ -84,7 +84,7 @@
         "english": "Gujarati",
         "native": "\u0a97\u0ac1\u0a9c\u0ab0\u0abe\u0aa4\u0ac0"
     },
-    "sr-CYRL": {
+    "sr-Cyrl": {
         "iso639_1": "sr",
         "english": "Serbian",
         "native": "\u0421\u0440\u043f\u0441\u043a\u0438"
@@ -404,7 +404,7 @@
         "english": "Arabic",
         "native": "\u0639\u0631\u0628\u064a"
     },
-    "sr-LATN": {
+    "sr-Latn": {
         "iso639_1": "sr",
         "english": "Serbian",
         "native": "Srpski"
diff --git a/migrations/203-fix-serbian-locale-codes.py b/migrations/203-fix-serbian-locale-codes.py
new file mode 100644
index 000000000..434fd1b93
--- /dev/null
+++ b/migrations/203-fix-serbian-locale-codes.py
@@ -0,0 +1,18 @@
+from gallery.models import Image, Video
+from users.models import Profile
+from wiki.models import Document, Locale
+
+
+def run():
+    """Fix casing in locale code for sr-Cyrl and sr-Latn."""
+    Document.objects.filter(locale='sr-CYRL').update(locale='sr-Cyrl')
+    Locale.objects.filter(locale='sr-CYRL').update(locale='sr-Cyrl')
+    Image.objects.filter(locale='sr-CYRL').update(locale='sr-Cyrl')
+    Video.objects.filter(locale='sr-CYRL').update(locale='sr-Cyrl')
+    Profile.objects.filter(locale='sr-CYRL').update(locale='sr-Cyrl')
+
+    Document.objects.filter(locale='sr-LATN').update(locale='sr-Latn')
+    Locale.objects.filter(locale='sr-LATN').update(locale='sr-Latn')
+    Image.objects.filter(locale='sr-LATN').update(locale='sr-Latn')
+    Video.objects.filter(locale='sr-LATN').update(locale='sr-Latn')
+    Profile.objects.filter(locale='sr-LATN').update(locale='sr-Latn')
diff --git a/settings.py b/settings.py
index 13c917280..97a086044 100644
--- a/settings.py
+++ b/settings.py
@@ -154,8 +154,8 @@ SUMO_LANGUAGES = (
     'sl',
     'son',
     'sq',
-    'sr-CYRL',
-    'sr-LATN',
+    'sr-Cyrl',
+    'sr-Latn',
     'sv',
     'ta-LK',
     'ta',