diff --git a/homeassistant/components/watson_tts/tts.py b/homeassistant/components/watson_tts/tts.py
index be60908d096..552083854a2 100644
--- a/homeassistant/components/watson_tts/tts.py
+++ b/homeassistant/components/watson_tts/tts.py
@@ -23,7 +23,7 @@ SUPPORTED_VOICES = [
     "de-DE_BirgitVoice",
     "de-DE_BirgitV2Voice",
     "de-DE_DieterVoice",
-    "de-DE_DieterV2Voice"
+    "de-DE_DieterV2Voice",
     "en-GB_KateVoice",
     "en-US_AllisonVoice",
     "en-US_AllisonV2Voice",