HMRC Personal Tax Account: What You Can Check, Claim and Fix

Your HMRC personal tax account is a free online account that shows what HMRC currently believes about your income, your tax code, your National Insurance record and your State Pension. You can use it to correct wrong information, claim several reliefs and refunds, and see whether you have overpaid — and you can set it up in about ten minutes at gov.uk/personal-tax-account. The account is for personal tax only; it does not cover company accounts or VAT.

Key points

• You need a Government Gateway user ID (or GOV.UK One Login) plus proof of identity to set the account up.
• It shows your tax code, employers and pay records, National Insurance record, State Pension forecast and any tax you owe or are owed.
• You can fix a wrong tax code, update estimated income, report a company car change and update your address from inside the account.
• Marriage Allowance, working-from-home relief, uniform flat-rate expenses and P800 refunds are all claimed online.
• Some things — bereavement, complex disputes, missing years no longer online — still need a phone call or a letter.

Setting up a personal tax account

Setting up a personal tax account is free and there is no need to pay anyone to do it for you. You register once and the same sign-in works every year.

What you need to hand

• Your National Insurance number.
• An email address and a mobile phone or authenticator app for security codes.
• Two forms of identity evidence. This is usually a UK passport, a UK photocard driving licence, a recent payslip or P60, or details from a credit file (a mortgage, loan or mobile contract).

If you already file a Self Assessment return, you almost certainly already have a Government Gateway ID — use that rather than creating a second one, because duplicate accounts are a common cause of "I can't see my record" problems. HMRC is moving sign-in to GOV.UK One Login, so the screens you see may differ from older guides.

Signing in afterwards

You sign in with your user ID, password and a security code. The HMRC app does most of the same jobs and is often quicker for checking a tax code or getting your National Insurance number on screen. If you have lost your user ID or password, the recovery process on the sign-in page uses your National Insurance number and email — you do not need to start again from scratch.

What you can see in your personal tax account

This is the part most people underuse. The account is essentially HMRC's version of your financial life, and it is the same data the tax calculation is built from.

Scottish taxpayers see an S prefix on the tax code (S1257L, for example). Scottish rates apply to non-savings income only — savings interest and dividends are taxed at UK rates wherever you live. If you have moved across the border and the prefix is missing or wrong, that is fixed by updating your address, not by changing the code directly.

What you can fix yourself

The account is not read-only. Several corrections that people assume need a phone call can be made in a few clicks.

• Your tax code. You can tell HMRC that a second job has ended, that you no longer receive a benefit, or that an estimated figure is wrong. HMRC then issues a new code to your employer, usually within a few days.
• Estimated pay. If your income has dropped or jumped, correcting the estimate stops HMRC collecting the wrong amount month by month.
• Company cars and medical insurance. Adding, removing or changing a company car adjusts the benefit figure in your code immediately rather than leaving it to a year-end reconciliation.
• Address and name. Important for Scottish or Welsh rate status and for any refund cheque.
• Missing employment or pension. If a job is missing entirely, your allowances may be sitting against the wrong source of income.

Worked example: a tax code left too low

Priya works in England and is on code 1000L instead of 1257L, because an old benefit-in-kind deduction was never removed.

1. Code 1000L gives £10,000 of tax-free pay; 1257L gives the full £12,570 Personal Allowance.
2. The difference is £12,570 − £10,000 = £2,570 of income taxed that should not have been.
3. At the 20% basic rate that is £2,570 × 0.20 = £514 too much tax for the year, or about £42.83 a month.

Correcting the code stops the overpayment going forward; the tax already paid comes back either through an adjusted code or as a refund after the year end. You can sanity-check your own code with the tax code checker before you contact HMRC, so you know what you are asking for.

Claiming refunds and reliefs

Most small personal tax reliefs are now claimed online rather than by post. The main ones handled through your account or the linked GOV.UK services are:

• Marriage Allowance — worth up to £252 in 2026/27 where one partner's income is below £12,570 and the other is a basic-rate taxpayer. Backdating up to four years can be worth around £1,260 in total. In Scotland the receiving partner needs to be paying the starter, basic or intermediate rate. Apply at gov.uk/marriage-allowance.
• Working-from-home relief — if your employer requires you to work at home, relief on £6 a week (£312 a year) is worth £62.40 a year at 20% and £124.80 at 40%.
• Uniform and flat-rate expenses — a nurse's £125 flat rate gives £25 back at 20%; the general uniform rate is £60. Higher amounts apply to some jobs.
• Mileage Allowance Relief — if your employer reimburses less than the approved rates for business miles in your own car.
• Higher-rate pension relief — personal pensions only add the basic 20% automatically, so 40% and 45% taxpayers need to claim the rest through Self Assessment or by contacting HMRC.

If HMRC has already worked out that you overpaid, you will see a P800 tax calculation, normally issued after the tax year ends. Where it shows a refund you can usually ask for it to be paid straight to your bank account from the account; if you do nothing, a cheque follows later. If you are not sure whether anything is sitting there, run through check if HMRC owes you money first — it covers the four-year claim window and the reliefs people most often miss.

Evidence rules for employment expense claims have tightened in recent years, so keep receipts for anything beyond the published flat rates.

When to call HMRC instead

The account cannot do everything. Contact HMRC directly if:

• You are dealing with the tax affairs of someone who has died.
• You disagree with a tax calculation, or want to appeal a penalty.
• Your National Insurance record has gaps you want to fill with voluntary Class 3 contributions at £18.40 a week and the online service will not quote for the years you need — voluntary contributions are normally limited to the last six tax years.
• Two records have merged or duplicated, or income shows against an employer you have never worked for (a possible sign of fraud).
• You cannot pass identity verification online, in which case HMRC can verify you another way.

Before calling, take a screenshot of the relevant screen and note your National Insurance number and the dates in question. Most tax code disputes are resolved faster when you can quote the exact figures HMRC is using.

One change worth flagging: Making Tax Digital for Income Tax starts in April 2026 for people with gross self-employment or property income above £50,000, which means quarterly updates through compatible software rather than a single annual return. Your personal tax account will still show the underlying PAYE and National Insurance data, but the filing itself moves elsewhere.

What to do next

Start with the code on your latest payslip. If it is anything other than the standard 1257L (or S1257L in Scotland), work out why using the tax code checker, then sign in to your personal tax account and correct the information behind it. If the code has been wrong for a while, follow that with check if HMRC owes you money to see how many of the last four tax years you can still reclaim.