Q. I am going to the USA in Oct 2013 and Feb 2014 and my full UK passport expires in Mar 2014, does the passport have to be valid under the six months clear rule or do I need to renew in September?

Peter Kendal

A. Renew in June 2013! There is no legal need to do so, since the US - unlike many other non-EU nations - has no minimum-validity stipulation for British passport holders. "Your passport should be valid for the proposed duration of your stay. You don't need any additional period of validity on your passport beyond this," says the Foreign Office.

But if you renew a passport within nine months of its expiry date, you get full credit for outstanding time. In other words, if your passport expires on 1 March 2014, and you renew it any time from 1 June 2013, the replacement will be valid until 1 March 2024. And the "Esta" (electronic permission to visit the US) you will require for the trips is valid for two years, or until the passport expires, whichever is the sooner. Indeed, the only reason I can see for not getting a fresh passport next month is if you already have an Esta that will be valid for your two forthcoming trips.

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