Where can I report motorway signs which are wrong?

I have taken to phoning 101 (the nationwide police non-emergency number) on each of the many occasions when I spot a set of overhead signs that are clearly wrong. Is there a more effective way of getting the Highways Agency to improve its act?

Asked on 5 October 2013 by BA, via email

Answered by Honest John
I don't know if it's the systems or the people. Possibly depends on who is on duty for that area that day. Some of them are dedicated and brilliant. Some of them are clearly nuts, but probably unsackable. The Highways Agency number to report errors is 0300 123 5000.
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