diff --git a/src/nm-ip4-config.c b/src/nm-ip4-config.c
index 8b1596dd0d..abc8af836a 100644
--- a/src/nm-ip4-config.c
+++ b/src/nm-ip4-config.c
@@ -1288,6 +1288,7 @@ nm_ip4_config_add_route (NMIP4Config *config, const NMPlatformIP4Route *new)
 			memcpy (item, new, sizeof (*item));
 			/* Restore highest priority source */
 			item->source = MAX (old_source, new->source);
+			item->ifindex = priv->ifindex;
 			goto NOTIFY;
 		}
 	}
diff --git a/src/nm-ip6-config.c b/src/nm-ip6-config.c
index 2077af81b3..9d4bf47b20 100644
--- a/src/nm-ip6-config.c
+++ b/src/nm-ip6-config.c
@@ -1289,6 +1289,7 @@ nm_ip6_config_add_route (NMIP6Config *config, const NMPlatformIP6Route *new)
 			*item = *new;
 			/* Restore highest priority source */
 			item->source = MAX (old_source, new->source);
+			item->ifindex = priv->ifindex;
 			goto NOTIFY;
 		}
 	}