Hi, thank you for your question. Are there any official documents in your new surname (eg. Passport?)
No you do not. You can use any name you want and there is no legal requirement to have a document. However, organisations such as banks, passport office and other official bodies will likely require evidence of your new name and this can be done either through a deed poll application (see here: https://www.gov.uk/change-name-deed-poll/overview) or if you complete a statutory declaration for a change of name (you can google for templates) and swear this at a local solicitors.
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