Got married, divorced or changed your name by deed poll? You'll need to tell HMRC so your tax records match your new legal name. It's quick, it's free, and there are four ways to do it.
This guide walks you through each method, how long it takes, and what happens if you put it off. We'll also cover the one thing people most often miss after a wedding: Marriage Allowance.
It's written for individuals and for the self-employed, contractors and landlords we look after at Zmartly.
Why do you need to tell HMRC about a name change? {#why-tell-hmrc}
HMRC uses your legal name to match your records across other government departments, to issue the right tax code, and to make sure correspondence reaches you. As gov.uk puts it, you need to tell HMRC if you've changed your name or address.
If your records are out of date, a few things can go wrong:
- You miss letters about your tax code, a return, or a payment due.
- Your name doesn't match your payroll or bank records, which can hold up refunds.
- You struggle to pass identity checks when you sign in or call.
There's also a money angle. If a letter about a Self Assessment return goes to the wrong place and you miss the 31 January online deadline, you get an automatic £100 penalty even if you owe no tax. That penalty applies as soon as the deadline passes, so keeping your details current is the cheapest insurance going. See gov.uk on Self Assessment penalties.
One rule before we start: never email your name change, National Insurance number or bank details to HMRC. Email isn't secure. Use the official online services, the app, the phone, or post.
Which method should you use? {#which-method}
You can change your name with HMRC online, through the app, by phone, or by post. Here's how they compare.
| Method | Typical processing time | What you need | Best for |
|---|---|---|---|
| Online (personal tax account) | A few working days | Government Gateway user ID and password | Fast, free updates with on-screen confirmation |
| HMRC app | A few working days | The official app plus Government Gateway login | Updating on your phone |
| Phone | Often during the call | NI number and security details | No online access, or a query to discuss |
| Post | Around 1 to 2 weeks | A signed letter and copies of evidence | A paper trail, or no internet or phone access |
For most people, online or the app is the simplest route. Phone suits anyone without online access. Post is the slowest, but it lets you send evidence upfront.
If you're deaf or hard of hearing, you can use Relay UK: dial 18001 before the HMRC number.
How do I change my name with HMRC online? {#online}
Book a free Tax Health Check →
The quickest way is through your personal tax account on gov.uk.
- Go to gov.uk and sign in to your personal tax account using your Government Gateway user ID and password.
- Find "Manage your personal details" (the exact wording changes from time to time).
- Select the option to change your name.
- Enter your new first name, any middle names, your new surname, and the date your name changed.
- Check everything, then submit. You'll get on-screen confirmation that your request has been received.
There isn't a separate standalone name change form. The function lives inside your personal tax account, and submitting it updates HMRC's records directly.
If you don't have a Government Gateway account, you can set one up during sign-in. You'll need your National Insurance number and a form of ID such as a passport or photocard driving licence. It takes around 10 minutes.
You don't have to say why your name changed. HMRC may ask for evidence later (a marriage certificate or deed poll, for example), so keep a copy handy.
Can I use the HMRC app? {#app}
Yes. The official HMRC app does the same job as the website, just on your phone. Download it free from the Apple App Store or Google Play, and only from those official stores.
Sign in with your Government Gateway credentials, open your profile or personal details, choose to change your name, enter your new details, and submit. Processing times are the same as the website, and you'll get on-screen confirmation.
The app is handy for the rest of your tax life too: you can check your tax code, see Self Assessment deadlines and make payments from it.
Can I call HMRC to change my name? {#phone}
Yes. Calling suits you if you don't have online access or you want to talk something through.
Call the Income Tax helpline on 0300 200 3300, Monday to Friday, 8am to 6pm (closed weekends and bank holidays). Relay UK users dial 18001 0300 200 3300.
Have these ready so the adviser can find you and verify your identity:
- Your National Insurance number
- Your current name as HMRC has it
- Your date of birth
- Your Unique Taxpayer Reference (UTR) if you're in Self Assessment
The adviser will ask security questions before changing anything. That's a good thing: it stops anyone else altering your records. Lines are busiest on Monday mornings and through January, so mid-week mid-morning is usually quieter.
How do I change my name with HMRC by post? {#post}
If you'd rather write, or you want to send evidence upfront, post works fine. Write to the address on the most recent letter you've had from HMRC, as different teams handle different taxes. If you have no recent letter, general post can go to HMRC, BX9 1AS.
Your letter should include:
- Your previous name, exactly as HMRC has it
- Your new legal name
- The date your name changed
- Your National Insurance number and date of birth
- Your UTR if you're registered for Self Assessment
- A note of the evidence you're enclosing
- Your signature and the date
Enclose a clear photocopy of your evidence, never the original: a marriage or civil partnership certificate, a deed poll, or a decree absolute if you're reverting to a former name. HMRC doesn't return documents.
It's worth getting free Proof of Posting from the Post Office, and keeping a copy of everything with your records.
How to change your name with HMRC after marriage {#marriage}
Changing your name after a wedding is the most common reason people contact HMRC, and the process is exactly the same as any other name change. Update online or in the app, enter your new name and the date it changed (usually your wedding date), and submit. You don't need to explain that it's because of marriage.
Keep your marriage certificate to hand in case HMRC asks for it later.
A couple of points worth knowing:
- You can't change your spouse's details for them. Each person updates their own record using their own login or NI number, even married couples, unless one of you is a registered tax agent for the other.
- HMRC doesn't tell anyone else. You'll still need to update your bank, employer, the DVLA, the passport office and others separately.
If you run a limited company, your name as a director is held by Companies House, not HMRC, so update that separately. For an overview of director duties, see our company secretarial services.
Illustrative example: updating after a wedding
This is a worked example to show the steps, not a real client.
Priya, an employed marketing manager who also lets out one property, marries in the 2025/26 tax year and takes her partner's surname. A few days after the wedding she signs in to her personal tax account, updates her name and the date it changed, and saves the on-screen confirmation.
A few working days later her account shows the new name. Because she updated HMRC and her employer's HR team at the same time, her payroll record and tax code line up, and her name flows straight through to her next Self Assessment return. No mismatches, no chasing.
Should you claim Marriage Allowance? {#marriage-allowance}
Marriage doesn't change how you're each taxed: you're still taxed on your own income. But it can unlock Marriage Allowance, which is easy to miss.
Marriage Allowance lets the lower earner transfer £1,260 of their Personal Allowance to a spouse or civil partner, worth up to £252 off the higher earner's tax bill for 2025/26. To qualify:
- You're married or in a civil partnership.
- The lower earner's income is below the Personal Allowance, usually £12,570 for 2025/26 (see gov.uk Income Tax rates and allowances).
- The higher earner is a basic rate taxpayer, with income usually between £12,571 and £50,270 for 2025/26 (see gov.uk Income Tax rates).
Apply through your personal tax account or the app. Once it's approved, it carries on automatically each year until your circumstances change or you cancel it. You can backdate a claim to the 2022/23 tax year if you were eligible, which can add up to a useful lump sum. Full conditions are on gov.uk's Marriage Allowance page.
Note that Scotland sets its own Income Tax bands, so the higher earner's band differs there. If you want to see what the allowance is worth alongside your wider tax position, our income tax calculator is a good starting point.
If your circumstances are more involved (rental income, dividends or self-employment on top of a salary), our self assessment service can keep your name, allowances and return all pulling in the same direction.
A quick word on Child Benefit
If your family situation has also changed, remember Child Benefit is handled separately, by the Child Benefit Office, not your general tax account. Child Benefit is currently £27.05 a week for your eldest or only child and £17.90 a week for each additional child (see gov.uk Child Benefit rates).
If you or your partner have adjusted net income over £60,000, the High Income Child Benefit Charge starts to claw it back, at 1% of the benefit for every £200 of income above £60,000, and cancels it out entirely at £80,000. The charge falls on whoever has the higher income, and you report it through Self Assessment. The detail is on gov.uk's Child Benefit tax charge page.
Need a hand keeping HMRC up to date?
Changing your name is straightforward, but lining up your tax code, allowances and return around a life change is where small mistakes cost money. Want it handled? Book a free 20-minute call with a Zmartly accountant and we'll make sure your records, and your tax, are right. Talk to a Zmartly accountant.
FAQs {#faqs}
How do I change my name with HMRC online?
Sign in to your personal tax account on gov.uk with your Government Gateway user ID and password, go to "Manage your personal details", select the option to change your name, enter your new name and the date it changed, then submit. You'll get on-screen confirmation, and the update usually takes a few working days. If you don't have a Government Gateway account, you can create one during sign-in using your National Insurance number and a form of ID.
What's the phone number to change my name with HMRC?
Call the Income Tax helpline on 0300 200 3300, open Monday to Friday, 8am to 6pm and closed at weekends and on bank holidays. Relay UK users dial 18001 0300 200 3300. Have your National Insurance number, date of birth and new name ready, as the adviser will ask security questions before updating your records.
Can I change my name with HMRC after marriage online?
Yes. The process is the same as any other name change: sign in to your personal tax account or the HMRC app, update your name and the date it changed, and submit. You don't need to say it was due to marriage. HMRC doesn't usually ask for your marriage certificate upfront, but keep a copy in case they request evidence later.
How long does it take HMRC to process a name change?
Online and app updates usually take a few working days, and phone updates are often done during the call. Postal changes take longer, typically around one to two weeks once you include delivery and processing, and longer in busy periods such as January. You can check your online account to see when the change has gone through.
What happens if I don't tell HMRC about a change of name or address?
Your records won't match other systems, so you may miss letters about your tax code, a return or a payment, and refunds can be delayed. If a missed letter means you file your Self Assessment return late, you face an automatic £100 penalty even if you owe no tax. You may also find it harder to pass identity checks online or by phone.
Can I change someone else's details with HMRC?
No, unless you're a registered tax agent with current authorisation, you hold power of attorney, or you're the personal representative of someone who has died. HMRC's security rules mean each person normally updates their own details using their own login or by passing security questions on the phone. Even spouses can't change each other's records without proper authorisation.
Do I need to tell HMRC if I move abroad?
Yes. Moving abroad can affect your tax residency and your UK tax position, so tell HMRC before you leave through your personal tax account, the app, or by calling 0300 200 3300. Give your new address and your leaving date. Keep a reliable UK correspondence address, such as your accountant's, so you still receive any final letters.
