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I am travelling to the UK but my UK passport is about to expire and so would like ot enter the UK with my US passport. How is allowed and legal?

marked as duplicate by Nate Eldredge, Nean Der Thal, drat, Doc, Mark Mayo May 25 '14 at 23:44

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    In principle, a country should allow any citizen to enter, and some countries consider expired passport to be sufficient proof of citizenship. So you may not have a problem at all (but you should obviously check) – Max May 25 '14 at 18:07

As explained in Do I have to enter the UK on my UK passport? using your UK passport is not mandatory. So you can certainly use your US passport if that's more convenient.

Furthermore, an expired British citizen passport is also enough to enter the UK and should be enough for the airline.

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