diff --git a/mu5001tool/__main__.py b/mu5001tool/__main__.py
index f27d637..56c4b3d 100644
--- a/mu5001tool/__main__.py
+++ b/mu5001tool/__main__.py
@@ -30,11 +30,12 @@ def run_status(m):
 sp_status = subparsers.add_parser("status", help="General modem status information")
 sp_status.set_defaults(func=run_status)
 
-def run_prometheus_exporter(m):
-    prometheus_exporter(m)
+def run_prometheus_exporter(m, listen_port):
+    prometheus_exporter(m, listen_port)
 
 sp_prometheus_exporter = subparsers.add_parser("prometheus-exporter", help="Serve metrics as prometheus exporter")
 sp_prometheus_exporter.set_defaults(func=run_prometheus_exporter)
+sp_prometheus_exporter.add_argument("--listen-port", dest="listen_port", type=int, default=9242, help="Port for service webserver")
 
 def main():
 
diff --git a/mu5001tool/prometheus_exporter.py b/mu5001tool/prometheus_exporter.py
index b03de09..df84b34 100644
--- a/mu5001tool/prometheus_exporter.py
+++ b/mu5001tool/prometheus_exporter.py
@@ -149,7 +149,7 @@ def make_prometheus_exporter_request_handler(m):
 
     return PrometheusExporterRequestHandler
 
-def prometheus_exporter(m):
-    with HTTPServerV6(("::1", 9242), make_prometheus_exporter_request_handler(m)) as httpd:
+def prometheus_exporter(m, listen_port):
+    with HTTPServerV6(("::1", listen_port), make_prometheus_exporter_request_handler(m)) as httpd:
         print("Starting prometheus exporter on http://[{}]:{}".format(*httpd.socket.getsockname()[:2]))
         httpd.serve_forever()