diff --git a/neqo-http3/src/connection.rs b/neqo-http3/src/connection.rs
index cfa78df787..24c9937dca 100644
--- a/neqo-http3/src/connection.rs
+++ b/neqo-http3/src/connection.rs
@@ -386,10 +386,16 @@ impl Http3Connection {
         Ok(())
     }
 
-    /// Inform a `HttpConnection` that a stream has data to send and that `send` should be called
-    /// for the stream.
-    pub fn stream_has_pending_data(&mut self, stream_id: StreamId) {
-        self.streams_with_pending_data.insert(stream_id);
+    /// Inform a [`Http3Connection`] that a stream might have data to send in
+    /// case `send` should be called for the stream.
+    pub fn stream_might_have_pending_data(&mut self, stream_id: StreamId) {
+        if self
+            .send_streams
+            .get(&stream_id)
+            .map_or(false, |s| s.has_data_to_send())
+        {
+            self.streams_with_pending_data.insert(stream_id);
+        }
     }
 
     /// Return true if there is a stream that needs to send data.
diff --git a/neqo-http3/src/connection_server.rs b/neqo-http3/src/connection_server.rs
index dcf759f177..1f1bf5923c 100644
--- a/neqo-http3/src/connection_server.rs
+++ b/neqo-http3/src/connection_server.rs
@@ -64,13 +64,15 @@ impl Http3ServerHandler {
         data: &[u8],
         conn: &mut Connection,
     ) -> Res<usize> {
-        self.base_handler.stream_has_pending_data(stream_id);
-        self.needs_processing = true;
-        self.base_handler
+        let n = self
+            .base_handler
             .send_streams
             .get_mut(&stream_id)
             .ok_or(Error::InvalidStreamId)?
-            .send_data(conn, data)
+            .send_data(conn, data)?;
+        self.base_handler.stream_might_have_pending_data(stream_id);
+        self.needs_processing = true;
+        Ok(n)
     }
 
     /// Supply response heeaders for a request.
@@ -87,7 +89,7 @@ impl Http3ServerHandler {
             .http_stream()
             .ok_or(Error::InvalidStreamId)?
             .send_headers(headers, conn)?;
-        self.base_handler.stream_has_pending_data(stream_id);
+        self.base_handler.stream_might_have_pending_data(stream_id);
         self.needs_processing = true;
         Ok(())
     }
@@ -100,7 +102,7 @@ impl Http3ServerHandler {
     pub fn stream_close_send(&mut self, stream_id: StreamId, conn: &mut Connection) -> Res<()> {
         qdebug!([self], "Close sending side stream={}.", stream_id);
         self.base_handler.stream_close_send(conn, stream_id)?;
-        self.base_handler.stream_has_pending_data(stream_id);
+        self.base_handler.stream_might_have_pending_data(stream_id);
         self.needs_processing = true;
         Ok(())
     }