diff --git a/cmd/swarm/main.go b/cmd/swarm/main.go
index 04930760ee..c4227d16ba 100644
--- a/cmd/swarm/main.go
+++ b/cmd/swarm/main.go
@@ -252,6 +252,10 @@ func registerBzzService(ctx *cli.Context, stack *node.Node) {
 	if len(bzzport) > 0 {
 		bzzconfig.Port = bzzport
 	}
+	networkId := ctx.GlobalUint64(SwarmNetworkIdFlag.Name)
+	if networkId > 0 {
+		bzzconfig.NetworkId = networkId
+	}
 	swapEnabled := ctx.GlobalBool(SwarmSwapEnabled.Name)
 	syncEnabled := ctx.GlobalBoolT(SwarmSyncEnabled.Name)