diff --git a/include/haproxy/mux_quic.h b/include/haproxy/mux_quic.h
index b91ccdcbd..425924212 100644
--- a/include/haproxy/mux_quic.h
+++ b/include/haproxy/mux_quic.h
@@ -25,7 +25,7 @@ void qcs_notify_send(struct qcs *qcs);
 struct buffer *qcc_get_stream_rxbuf(struct qcs *qcs);
 struct buffer *qcc_get_stream_txbuf(struct qcs *qcs);
 void qcc_reset_stream(struct qcs *qcs, int err);
-void qcc_send_stream(struct qcs *qcs, int urg);
+void qcc_send_stream(struct qcs *qcs, int urg, int count);
 void qcc_abort_stream_read(struct qcs *qcs);
 int qcc_recv(struct qcc *qcc, uint64_t id, uint64_t len, uint64_t offset,
              char fin, char *data);
diff --git a/src/h3.c b/src/h3.c
index 424ecd833..00eed1259 100644
--- a/src/h3.c
+++ b/src/h3.c
@@ -1476,7 +1476,7 @@ static int h3_control_send(struct qcs *qcs, void *ctx)
 	ret = b_force_xfer(res, &pos, b_data(&pos));
 	if (ret > 0) {
 		/* Register qcs for sending before other streams. */
-		qcc_send_stream(qcs, 1);
+		qcc_send_stream(qcs, 1, ret);
 		h3c->flags |= H3_CF_SETTINGS_SENT;
 	}
 
@@ -2213,6 +2213,7 @@ static int h3_send_goaway(struct h3c *h3c)
 	struct buffer pos, *res;
 	unsigned char data[3 * QUIC_VARINT_MAX_SIZE];
 	size_t frm_len = quic_int_getsize(h3c->id_goaway);
+	size_t xfer;
 
 	TRACE_ENTER(H3_EV_H3C_END, h3c->qcc->conn);
 
@@ -2234,8 +2235,8 @@ static int h3_send_goaway(struct h3c *h3c)
 		goto err;
 	}
 
-	b_force_xfer(res, &pos, b_data(&pos));
-	qcc_send_stream(qcs, 1);
+	xfer = b_force_xfer(res, &pos, b_data(&pos));
+	qcc_send_stream(qcs, 1, xfer);
 
 	h3c->flags |= H3_CF_GOAWAY_SENT;
 	TRACE_LEAVE(H3_EV_H3C_END, h3c->qcc->conn);
diff --git a/src/mux_quic.c b/src/mux_quic.c
index 55c395a09..b75d4fff7 100644
--- a/src/mux_quic.c
+++ b/src/mux_quic.c
@@ -963,15 +963,16 @@ void qcc_reset_stream(struct qcs *qcs, int err)
 		qcs_alert(qcs);
 	}
 
-	qcc_send_stream(qcs, 1);
+	qcc_send_stream(qcs, 1, 0);
 	tasklet_wakeup(qcc->wait_event.tasklet);
 }
 
 /* Register <qcs> stream for emission of STREAM, STOP_SENDING or RESET_STREAM.
  * Set <urg> to 1 if stream content should be treated in priority compared to
- * other streams.
+ * other streams. For STREAM emission, <count> must contains the size of the
+ * frame payload.
  */
-void qcc_send_stream(struct qcs *qcs, int urg)
+void qcc_send_stream(struct qcs *qcs, int urg, int count)
 {
 	struct qcc *qcc = qcs->qcc;
 
@@ -1005,7 +1006,7 @@ void qcc_abort_stream_read(struct qcs *qcs)
 	TRACE_STATE("abort stream read", QMUX_EV_QCS_END, qcc->conn, qcs);
 	qcs->flags |= (QC_SF_TO_STOP_SENDING|QC_SF_READ_ABORTED);
 
-	qcc_send_stream(qcs, 1);
+	qcc_send_stream(qcs, 1, 0);
 	tasklet_wakeup(qcc->wait_event.tasklet);
 
  end:
@@ -2804,6 +2805,7 @@ static size_t qmux_strm_snd_buf(struct stconn *sc, struct buffer *buf,
                                 size_t count, int flags)
 {
 	struct qcs *qcs = __sc_mux_strm(sc);
+	const size_t old_data = b_data(&qcs->tx.buf);
 	size_t ret = 0;
 	char fin;
 
@@ -2829,7 +2831,7 @@ static size_t qmux_strm_snd_buf(struct stconn *sc, struct buffer *buf,
 	}
 
 	if (ret || fin) {
-		qcc_send_stream(qcs, 0);
+		qcc_send_stream(qcs, 0, b_data(&qcs->tx.buf) - old_data);
 		if (!(qcs->qcc->wait_event.events & SUB_RETRY_SEND))
 			tasklet_wakeup(qcs->qcc->wait_event.tasklet);
 	}
@@ -2910,7 +2912,7 @@ static size_t qmux_strm_done_ff(struct stconn *sc)
 	struct qcs *qcs = __sc_mux_strm(sc);
 	struct qcc *qcc = qcs->qcc;
 	struct sedesc *sd = qcs->sd;
-	size_t total = 0;
+	size_t total = 0, data = sd->iobuf.data;
 
 	TRACE_ENTER(QMUX_EV_STRM_SEND, qcs->qcc->conn, qcs);
 
@@ -2922,9 +2924,10 @@ static size_t qmux_strm_done_ff(struct stconn *sc)
 	if (!(qcs->flags & QC_SF_FIN_STREAM) && !sd->iobuf.data)
 		goto end;
 
+	data += sd->iobuf.offset;
 	total = qcs->qcc->app_ops->done_ff(qcs);
 
-	qcc_send_stream(qcs, 0);
+	qcc_send_stream(qcs, 0, data);
 	if (!(qcs->qcc->wait_event.events & SUB_RETRY_SEND))
 		tasklet_wakeup(qcc->wait_event.tasklet);
 
@@ -3012,7 +3015,7 @@ static void qmux_strm_shutw(struct stconn *sc, enum co_shw_mode mode)
 				TRACE_STATE("set FIN STREAM",
 				            QMUX_EV_STRM_SHUT, qcc->conn, qcs);
 				qcs->flags |= QC_SF_FIN_STREAM;
-				qcc_send_stream(qcs, 0);
+				qcc_send_stream(qcs, 0, 0);
 			}
 		}
 		else {