diff --git a/nameko_grpc/streams.py b/nameko_grpc/streams.py
index 1802d48..348f915 100644
--- a/nameko_grpc/streams.py
+++ b/nameko_grpc/streams.py
@@ -168,7 +168,7 @@ def headers_to_send(self, defer_until_data=True):
         if self.headers_sent or len(self.headers) == 0:
             return False
 
-        if defer_until_data and self.queue.empty() and self.buffer.empty():
+        if defer_until_data and self.queue.empty():
             return False
 
         self.headers_sent = True