diff --git a/include/haproxy/connection-t.h b/include/haproxy/connection-t.h
index 88534dc63..a603966e5 100644
--- a/include/haproxy/connection-t.h
+++ b/include/haproxy/connection-t.h
@@ -670,6 +670,7 @@ struct mux_proto_list {
 	enum proto_proxy_mode mode;
 	enum proto_proxy_side side;
 	const struct mux_ops *mux;
+	const char *alpn;          /* Default alpn to set by default when the mux protocol is forced (optional, in binary form) */
 	struct list list;
 };
 
diff --git a/src/mux_h1.c b/src/mux_h1.c
index 30dcb6086..7b9cddf8d 100644
--- a/src/mux_h1.c
+++ b/src/mux_h1.c
@@ -5987,7 +5987,7 @@ static const struct mux_ops mux_h1_ops = {
 static struct mux_proto_list mux_proto_h1 =
 	{ .token = IST("h1"), .mode = PROTO_MODE_HTTP, .side = PROTO_SIDE_BOTH, .mux = &mux_h1_ops };
 static struct mux_proto_list mux_proto_http =
-	{ .token = IST(""), .mode = PROTO_MODE_HTTP, .side = PROTO_SIDE_BOTH, .mux = &mux_http_ops };
+	{ .token = IST(""), .mode = PROTO_MODE_HTTP, .side = PROTO_SIDE_BOTH, .mux = &mux_http_ops,  .alpn = "\010http/1.1" };
 
 INITCALL1(STG_REGISTER, register_mux_proto, &mux_proto_h1);
 INITCALL1(STG_REGISTER, register_mux_proto, &mux_proto_http);
diff --git a/src/mux_h2.c b/src/mux_h2.c
index 2a57f41a8..39119ce4f 100644
--- a/src/mux_h2.c
+++ b/src/mux_h2.c
@@ -8717,7 +8717,7 @@ static const struct mux_ops h2_ops = {
 };
 
 static struct mux_proto_list mux_proto_h2 =
-	{ .token = IST("h2"), .mode = PROTO_MODE_HTTP, .side = PROTO_SIDE_BOTH, .mux = &h2_ops };
+	{ .token = IST("h2"), .mode = PROTO_MODE_HTTP, .side = PROTO_SIDE_BOTH, .mux = &h2_ops,  .alpn = "\002h2" };
 
 INITCALL1(STG_REGISTER, register_mux_proto, &mux_proto_h2);