diff --git a/breakglass.go b/breakglass.go
index 2d5f04a..300be3c 100644
--- a/breakglass.go
+++ b/breakglass.go
@@ -32,6 +32,10 @@ var (
 		"/perm/breakglass.host_key",
 		"path to a PEM-encoded RSA, DSA or ECDSA private key (create using e.g. ssh-keygen -f /perm/breakglass.host_key -N '' -t rsa)")
 
+	port = flag.String("port",
+		"22",
+		"port for breakglass to listen on")
+
 	forwarding = flag.String("forward",
 		"",
 		"allow port forwarding. Use `loopback` for loopback interfaces and `private-network` for private networks")
@@ -191,7 +195,7 @@ func main() {
 	}
 
 	for _, addr := range addrs {
-		hostport := net.JoinHostPort(addr, "22")
+		hostport := net.JoinHostPort(addr, *port)
 		listener, err := net.Listen("tcp", hostport)
 		if err != nil {
 			log.Fatal(err)