diff --git a/src/h3.c b/src/h3.c
index 50e6b4f81..59e57c2bf 100644
--- a/src/h3.c
+++ b/src/h3.c
@@ -680,7 +680,7 @@ static ssize_t h3_headers_to_htx(struct qcs *qcs, const struct buffer *buf,
 	htx_to_buf(htx, &htx_buf);
 	htx = NULL;
 
-	if (!qc_attach_sc(qcs, &htx_buf)) {
+	if (!qc_attach_sc(qcs, &htx_buf, fin)) {
 		h3c->err = H3_INTERNAL_ERROR;
 		len = -1;
 		goto out;
diff --git a/src/hq_interop.c b/src/hq_interop.c
index cbbf47288..f34657854 100644
--- a/src/hq_interop.c
+++ b/src/hq_interop.c
@@ -88,7 +88,7 @@ static ssize_t hq_interop_decode_qcs(struct qcs *qcs, struct buffer *b, int fin)
 	htx_add_endof(htx, HTX_BLK_EOH);
 	htx_to_buf(htx, &htx_buf);
 
-	if (!qc_attach_sc(qcs, &htx_buf))
+	if (!qc_attach_sc(qcs, &htx_buf, fin))
 		return -1;
 
 	b_free(&htx_buf);
diff --git a/src/mux_quic.c b/src/mux_quic.c
index 3cc24108d..c4b695754 100644
--- a/src/mux_quic.c
+++ b/src/mux_quic.c
@@ -639,7 +639,7 @@ static struct qcs *qcc_init_stream_remote(struct qcc *qcc, uint64_t id)
 	return NULL;
 }
 
-struct stconn *qc_attach_sc(struct qcs *qcs, struct buffer *buf)
+struct stconn *qc_attach_sc(struct qcs *qcs, struct buffer *buf, char fin)
 {
 	struct qcc *qcc = qcs->qcc;
 	struct session *sess = qcc->conn->owner;
@@ -679,6 +679,11 @@ struct stconn *qc_attach_sc(struct qcs *qcs, struct buffer *buf)
 	BUG_ON_HOT(!LIST_INLIST(&qcs->el_opening));
 	LIST_DEL_INIT(&qcs->el_opening);
 
+	if (fin) {
+		TRACE_STATE("report end-of-input", QMUX_EV_STRM_RECV, qcc->conn, qcs);
+		se_fl_set(qcs->sd, SE_FL_EOI);
+	}
+
 	return qcs->sd->sc;
 }
 
@@ -2717,7 +2722,7 @@ static size_t qc_recv_buf(struct stconn *sc, struct buffer *buf,
 	else {
 		se_fl_clr(qcs->sd, SE_FL_RCV_MORE | SE_FL_WANT_ROOM);
 
-		/* Set end-of-input if FIN received and all data extracted. */
+		/* Set end-of-input when full message properly received. */
 		if (fin) {
 			TRACE_STATE("report end-of-input", QMUX_EV_STRM_RECV, qcc->conn, qcs);
 			se_fl_set(qcs->sd, SE_FL_EOI);