diff --git a/homeassistant/components/watson_tts/tts.py b/homeassistant/components/watson_tts/tts.py
index cdcbbc6ed2a..610ad61132e 100644
--- a/homeassistant/components/watson_tts/tts.py
+++ b/homeassistant/components/watson_tts/tts.py
@@ -191,7 +191,7 @@ class WatsonTTSProvider(Provider):
     def get_tts_audio(self, message, language=None, options=None):
         """Request TTS file from Watson TTS."""
         response = self.service.synthesize(
-            message, accept=self.output_format, voice=self.default_voice
+            text=message, accept=self.output_format, voice=self.default_voice
         ).get_result()
 
         return (CONTENT_TYPE_EXTENSIONS[self.output_format], response.content)