Changing your name in the UK is simpler than many people expect. In England, Wales and Northern Ireland, the standard route is a deed poll: a legal document that proves you have given up your old name and adopted a new one. You do not need a court order to change your name, and for most people the whole process can be completed in a single day. What matters is choosing the right type of deed poll, following the signing rules, and then updating your records with the organisations that hold them.

A deed poll is a written declaration, signed as a deed, in which you state that you have abandoned your former name and will use your new name for all purposes. Once it is signed and witnessed, it is the evidence you show to HM Passport Office, the DVLA, your bank, your employer and everyone else who holds your records. GOV.UK describes it plainly as a legal document that proves a change of name. It is the document behind most name changes in the UK, whether someone is changing a first name, a surname, a middle name, adding or removing a name, or correcting a spelling.

There are limits on what you can call yourself. Your new name must be pronounceable, and it must not include symbols, numbers or punctuation, although a hyphen in a hyphenated name and an apostrophe in an established name such as O'Hara are accepted. It must not be offensive or against the public interest, so adding a word such as Ltd to the end of your name is not allowed. A deed poll also cannot change which letters of your name are capitalised, and it cannot change your title, so Mr, Mrs, Sir, Lady or Doctor cannot be altered this way. If you are a permanent resident overseas, you cannot change your name by deed poll under the UK system.

Not every name change needs a deed poll at all. If you marry or enter a civil partnership and want to take your spouse's or civil partner's surname, you do not need one: you simply send a copy of your marriage or civil partnership certificate to the organisations that hold your records. If you divorce or end a civil partnership, you may be able to go back to your original name by showing your marriage certificate and decree absolute, or your civil partnership certificate and final order. Some organisations, however, will not change your name back without a deed poll, so if one refuses, a deed poll settles the question.

There are two kinds of deed poll, and choosing between them is the most important decision in the process. If you are 16 or over, you can make a deed poll yourself and start using your new name straight away. This is called an unenrolled deed poll. If you are 18 or over, you can also apply to put your name change on public record through the High Court. This is called an enrolled deed poll, and it costs £53.05. The difference matters because some organisations, including some banks, mobile phone companies and energy providers, will only accept an enrolled deed poll as proof of a new name. Before you decide, it is worth asking the organisations you deal with which type they will accept.

Making your own unenrolled deed poll costs nothing if you write it yourself. GOV.UK publishes the exact wording to use, with square brackets marking the details you replace with your own. You need two witnesses to sign it, and they must be 18 or over. Some organisations will not accept a deed poll if a witness lives at the same address as you or is a close relative, so choose witnesses who are independent where you can. The deed declares that you have given up your old name and adopted your new name for all purposes, and it is signed by you in both your old name and your new name, in the presence of both witnesses, who also sign. Once it is signed, you can use it straight away as proof of your new name. A specialist agency or a solicitor can also make the deed poll for you, and they may charge a fee for doing so.

Enrolling a deed poll puts your new name on public record with the High Court, and the process is more involved. You can apply online or by post, and the fee is £53.05. A public record of your name change and your address will be published in The Gazette, the official public record. If you have a strong reason why your details should not be published, explain it in your application; the judge may agree to publish only your first name or surname. You will be sent a copy of your Gazette notice by email or post. It can take several months to enrol a deed poll, and you can ask the Deed Poll Office for an update on your application six months after you apply.

To enrol online, you need a debit or credit card, and you will be told how to pay after submitting your application. HM Courts and Tribunals Service will review your application and email you three forms: LOC020, LOC021 and LOC027. Form LOC020 must be signed in front of two witnesses, while forms LOC021 and LOC027 must be signed in front of a solicitor. You then post the completed forms to the Deed Poll Office at the King's Bench Division, Room E15, the Royal Courts of Justice, Strand, London WC2A 2LL. Once you start an online application, you must submit it within 28 days or you will have to start again. You can apply by post instead, using the same three forms, and pay the fee by card through the High Court Fees Office or by postal order or cheque payable to HM Courts and Tribunals Service. Before you apply, you will need a copy of your birth certificate, a valid passport or a certificate of naturalisation, and you may also be asked for supporting documents such as adoption papers, a marriage or civil partnership certificate, or your partner's written consent.

Changing a child's name follows stricter rules. To change the name of a child under 18, you can either make an unenrolled deed poll through a specialist deed poll agency or a solicitor, or enrol a deed poll with the High Court. You will need either the agreement of everyone with parental responsibility, or a court order, and you must try to reach an agreement before you seek a court order. The enrolled route costs £53.05 and can take several months, and the child's new name will be published in The Gazette unless there is a strong reason to withhold it. If your child is aged 16 or 17, you must include a letter from them saying they agree to the change, witnessed and signed by someone aged 18 or over who is not related to the child. If a 16- or 17-year-old is married or in a civil partnership, or has been in the past, they need to enrol a deed poll as an adult instead.

A deed poll on its own does not update your passport or driving licence. You must apply separately to HM Passport Office and to the DVLA, using the deed poll as evidence. The same applies to your bank, your employer, HMRC, your council, your GP, your utility providers and your mobile phone company. A sensible order is to start with an organisation that will put the new name in writing, such as HMRC or your council, and then use that record alongside the deed poll when you update your passport and driving licence. Keep several certified copies of your deed poll, because many organisations will want to see the original or a certified copy, and you cannot be in two places at once.

One group has an extra duty. If you are a registered sex offender, violent offender or terrorist offender, you must tell the police you have changed your name within three days. You must go to your local prescribed police station to do this, and you will have been told where it is on release. It is a criminal offence not to tell the police. In Scotland, the rules are different again: a name change can be recorded against your birth entry through National Records of Scotland, so if you were born in Scotland or live there, check the Scottish rules rather than following the England and Wales route.

The cost of changing your name can therefore be nothing at all, if you write your own unenrolled deed poll, or £53.05 if you enrol it with the High Court, plus any fee a solicitor or agency charges if you ask one to prepare it for you. The unenrolled route takes effect the day you sign; the enrolled route takes several months and ends with a sealed deed sent back to you by post. Before you start, check the current fee and the current forms on GOV.UK, because fees and procedures change. A deed poll is a straightforward legal tool, but it is also a legal document, and if your situation is complicated, for example if there is a dispute over a child's name, getting advice from a solicitor is worth the cost.