diff --git a/src/proto.rs b/src/proto.rs
index 46a9cb107..c44a26f60 100644
--- a/src/proto.rs
+++ b/src/proto.rs
@@ -282,7 +282,7 @@ impl Codec for StreamFrame {
         } else {
             0
         };
-        buf.put_u8(0x10 | has_offset | has_len);
+        buf.put_u8(0x10 | has_offset | has_len | is_fin);
         if let Some(offset) = self.offset {
             VarLen::new(offset).encode(buf);
         }