diff --git a/src/connection.c b/src/connection.c
index be03b0d47..6dbca2c12 100644
--- a/src/connection.c
+++ b/src/connection.c
@@ -213,6 +213,13 @@ int conn_notify_mux(struct connection *conn, int old_flags, int forced_wake)
 			goto done;
 
 		if (conn_in_list) {
+			if (srv->cur_admin & SRV_ADMF_MAINT) {
+				/* Do not store an idle conn if server in maintenance. */
+				conn->mux->destroy(conn->ctx);
+				ret = -1;
+				goto done;
+			}
+
 			HA_SPIN_LOCK(IDLE_CONNS_LOCK, &idle_conns[tid].idle_conns_lock);
 			_srv_add_idle(srv, conn, conn_in_list == CO_FL_SAFE_LIST);
 			HA_SPIN_UNLOCK(IDLE_CONNS_LOCK, &idle_conns[tid].idle_conns_lock);
diff --git a/src/mux_fcgi.c b/src/mux_fcgi.c
index 0b143b893..949ef19c1 100644
--- a/src/mux_fcgi.c
+++ b/src/mux_fcgi.c
@@ -3091,11 +3091,21 @@ struct task *fcgi_io_cb(struct task *t, void *ctx, unsigned int state)
 	if (!ret && conn_in_list) {
 		struct server *srv = __objt_server(conn->target);
 
-		HA_SPIN_LOCK(IDLE_CONNS_LOCK, &idle_conns[tid].idle_conns_lock);
-		_srv_add_idle(srv, conn, conn_in_list == CO_FL_SAFE_LIST);
-		HA_SPIN_UNLOCK(IDLE_CONNS_LOCK, &idle_conns[tid].idle_conns_lock);
+		if (!(srv->cur_admin & SRV_ADMF_MAINT)) {
+			HA_SPIN_LOCK(IDLE_CONNS_LOCK, &idle_conns[tid].idle_conns_lock);
+			_srv_add_idle(srv, conn, conn_in_list == CO_FL_SAFE_LIST);
+			HA_SPIN_UNLOCK(IDLE_CONNS_LOCK, &idle_conns[tid].idle_conns_lock);
+		}
+		else {
+			/* Do not store an idle conn if server in maintenance. */
+			goto release;
+		}
 	}
 	return t;
+
+ release:
+	fcgi_release(fconn);
+	return NULL;
 }
 
 /* callback called on any event by the connection handler.
diff --git a/src/mux_h1.c b/src/mux_h1.c
index a8a6efa93..8aeec3931 100644
--- a/src/mux_h1.c
+++ b/src/mux_h1.c
@@ -4328,11 +4328,21 @@ struct task *h1_io_cb(struct task *t, void *ctx, unsigned int state)
 	if (!ret && conn_in_list) {
 		struct server *srv = __objt_server(conn->target);
 
-		HA_SPIN_LOCK(IDLE_CONNS_LOCK, &idle_conns[tid].idle_conns_lock);
-		_srv_add_idle(srv, conn, conn_in_list == CO_FL_SAFE_LIST);
-		HA_SPIN_UNLOCK(IDLE_CONNS_LOCK, &idle_conns[tid].idle_conns_lock);
+		if (!(srv->cur_admin & SRV_ADMF_MAINT)) {
+			HA_SPIN_LOCK(IDLE_CONNS_LOCK, &idle_conns[tid].idle_conns_lock);
+			_srv_add_idle(srv, conn, conn_in_list == CO_FL_SAFE_LIST);
+			HA_SPIN_UNLOCK(IDLE_CONNS_LOCK, &idle_conns[tid].idle_conns_lock);
+		}
+		else {
+			/* Do not store an idle conn if server in maintenance. */
+			goto release;
+		}
 	}
 	return t;
+
+ release:
+	h1_release(h1c);
+	return NULL;
 }
 
 static int h1_wake(struct connection *conn)
diff --git a/src/mux_h2.c b/src/mux_h2.c
index 9ae45d261..bf678e26e 100644
--- a/src/mux_h2.c
+++ b/src/mux_h2.c
@@ -4995,14 +4995,25 @@ struct task *h2_io_cb(struct task *t, void *ctx, unsigned int state)
 	if (!ret && conn_in_list) {
 		struct server *srv = __objt_server(conn->target);
 
-		HA_SPIN_LOCK(IDLE_CONNS_LOCK, &idle_conns[tid].idle_conns_lock);
-		_srv_add_idle(srv, conn, conn_in_list == CO_FL_SAFE_LIST);
-		HA_SPIN_UNLOCK(IDLE_CONNS_LOCK, &idle_conns[tid].idle_conns_lock);
+		if (!(srv->cur_admin & SRV_ADMF_MAINT)) {
+			HA_SPIN_LOCK(IDLE_CONNS_LOCK, &idle_conns[tid].idle_conns_lock);
+			_srv_add_idle(srv, conn, conn_in_list == CO_FL_SAFE_LIST);
+			HA_SPIN_UNLOCK(IDLE_CONNS_LOCK, &idle_conns[tid].idle_conns_lock);
+		}
+		else {
+			/* Do not store an idle conn if server in maintenance. */
+			goto release;
+		}
 	}
 
-leave:
+ leave:
 	TRACE_LEAVE(H2_EV_H2C_WAKE);
 	return t;
+
+ release:
+	TRACE_LEAVE(H2_EV_H2C_WAKE);
+	h2_release(h2c);
+	return NULL;
 }
 
 /* callback called on any event by the connection handler.
diff --git a/src/mux_spop.c b/src/mux_spop.c
index 95000e02b..77ee3a242 100644
--- a/src/mux_spop.c
+++ b/src/mux_spop.c
@@ -2587,11 +2587,21 @@ static struct task *spop_io_cb(struct task *t, void *ctx, unsigned int state)
 	if (!ret && conn_in_list) {
 		struct server *srv = __objt_server(conn->target);
 
-		HA_SPIN_LOCK(IDLE_CONNS_LOCK, &idle_conns[tid].idle_conns_lock);
-		_srv_add_idle(srv, conn, conn_in_list == CO_FL_SAFE_LIST);
-		HA_SPIN_UNLOCK(IDLE_CONNS_LOCK, &idle_conns[tid].idle_conns_lock);
+		if (!(srv->cur_admin & SRV_ADMF_MAINT)) {
+			HA_SPIN_LOCK(IDLE_CONNS_LOCK, &idle_conns[tid].idle_conns_lock);
+			_srv_add_idle(srv, conn, conn_in_list == CO_FL_SAFE_LIST);
+			HA_SPIN_UNLOCK(IDLE_CONNS_LOCK, &idle_conns[tid].idle_conns_lock);
+		}
+		else {
+			/* Do not store an idle conn if server in maintenance. */
+			goto release;
+		}
 	}
 	return t;
+
+ release:
+	spop_release(spop_conn);
+	return NULL;
 }
 
 /* callback called on any event by the connection handler.
diff --git a/src/server.c b/src/server.c
index b469b7ca8..d736362f7 100644
--- a/src/server.c
+++ b/src/server.c
@@ -7327,6 +7327,7 @@ int srv_add_to_idle_list(struct server *srv, struct connection *conn, int is_saf
 	 */
 	if (!(conn->flags & CO_FL_PRIVATE) &&
 	    srv && srv->pool_purge_delay > 0 &&
+	    !(srv->cur_admin & SRV_ADMF_MAINT) &&
 	    ((srv->proxy->options & PR_O_REUSE_MASK) != PR_O_REUSE_NEVR) &&
 	    ha_used_fds < global.tune.pool_high_count &&
 	    (srv->max_idle_conns == -1 || srv->max_idle_conns > srv->curr_idle_conns) &&
diff --git a/src/ssl_sock.c b/src/ssl_sock.c
index fc4e5a602..9342bd6d1 100644
--- a/src/ssl_sock.c
+++ b/src/ssl_sock.c
@@ -6478,12 +6478,22 @@ struct task *ssl_sock_io_cb(struct task *t, void *context, unsigned int state)
 #endif
 leave:
 	if (!ret && conn_in_list) {
-		struct server *srv = objt_server(conn->target);
+		struct server *srv = __objt_server(conn->target);
 
-		TRACE_DEVEL("adding conn back to idle list", SSL_EV_CONN_IO_CB, conn);
-		HA_SPIN_LOCK(IDLE_CONNS_LOCK, &idle_conns[tid].idle_conns_lock);
-		_srv_add_idle(srv, conn, conn_in_list == CO_FL_SAFE_LIST);
-		HA_SPIN_UNLOCK(IDLE_CONNS_LOCK, &idle_conns[tid].idle_conns_lock);
+		if (!(srv->cur_admin & SRV_ADMF_MAINT)) {
+			TRACE_DEVEL("adding conn back to idle list", SSL_EV_CONN_IO_CB, conn);
+			HA_SPIN_LOCK(IDLE_CONNS_LOCK, &idle_conns[tid].idle_conns_lock);
+			_srv_add_idle(srv, conn, conn_in_list == CO_FL_SAFE_LIST);
+			HA_SPIN_UNLOCK(IDLE_CONNS_LOCK, &idle_conns[tid].idle_conns_lock);
+		}
+		else {
+			/* Do not store an idle conn if server in maintenance. */
+
+			/* Connection is idle which means MUX layer is already initialized. */
+			BUG_ON(!conn->mux);
+			conn->mux->destroy(conn->ctx);
+			t = NULL;
+		}
 	}
 	TRACE_LEAVE(SSL_EV_CONN_IO_CB, conn);
 	return t;