If you get married or enter into a civil partnership, you may need to change your UK passport. This is not always necessary, but there are some instances when you have to amend it to reflect a name change. This may need to be planned in advance of any overseas travel you take shortly after the wedding, depending on when you want the change to be registered.
No change of maiden name
If you are not planning on changing from your maiden name to your married name, then you do not need to do anything with your existing passport. You can carry on using it as usual when you travel overseas even if you change your marital status. The trigger here is a legal change of name. If that happens, you need to amend your passport either before or after the ceremony.
Changing to a married name before a wedding
If you want to change your passport to your married name before the ceremony, then you can apply up to three months in advance. This involves surrendering your current copy to the Passport Office and applying for one in your new name. You need to complete a standard application form and the "Passports for newly weds and civil partners" form, PD2 (see resources). The PD2 is partly completed by the applicant, but there is a section that needs to be filled in and signed by the registrar or minister who will perform your ceremony. You will be given a post-dated passport valid from the date you get married. This will cover you for 10 years and, possibly, up to a further nine months, depending on how long you have left on your existing copy.
Changing to a married name after a wedding
If you decide to change your passport after your ceremony, then you simply need to fill in a standard application form as usual. You do, however, also need to send in your marriage or civil partnership certificate as proof of your change of status and name. If you opt to wait, you will travel in your maiden name.
If you want to change your passport before you get married, you will effectively have a period when you cannot travel overseas. The new passport in your married name will be post-dated and will only be valid from the date of the ceremony. Your maiden name copy will be cancelled. If you are planning to travel overseas in this period, it may be better to wait until after your wedding to make the change. If you need a visa for your honeymoon, you also need to check if this will be given on a post-dated passport. Some countries will not authorise this. A new passport can also invalidate any unexpired visas you had in your old one. Finally, you need to ensure that your passport - old or new - matches the name in which your holiday and flights were booked. If you book in your maiden name, you may not be able to travel on a new married name passport and vice versa.