Do you think you have overpaid tax?

You may have paid too much tax if:

  • you started a new job and had an emergency tax code for a while
  • your employer has had wrong tax code for you
  • you only had a job for part of the tax year
  • you had more than one job at the same time
  • you are a student and you only worked during the holidays
  • your circumstances changed – for example, you changed from full-time to part-time work

In these situations, HMRC’s P800 tax calculation system, may mean you do not need to claim a repayment, as HMRC might issue repayment automatically. If you have not received a P800 tax calculation from HMRC, and you have overpaid tax, you will need to make a claim for a tax repayment.

What is a P800 tax calculation?

Throughout the tax year, your employer gives HMRC details of how much income you have received, how much tax you have paid and the value of any benefits-in-kind you have received during the tax year.

Using this information, HMRC carry out an automatic reconciliation at the end of each tax year. This means that they put together all of the information they have received to work out whether or not you have paid the right amount of tax. If HMRC think you have not paid the right amount of tax, they send you a P800 tax calculation. This calculation will show you what tax HMRC think you should have paid. P800s are generally sent out between June and October after the end of the tax year in question.

You must always check your P800 tax calculation carefully, as HMRC may not have all the information they need to calculate your tax correctly, or they may have inaccurate information.

If you think you have paid too much tax, but you have not received a P800, you should tell HMRC why you think you have paid too much before the end of the tax year.

You can do this online, using your Personal Tax Account.

If you prefer to telephone HMRC, the helpline can be found on GOV.UK.

Contacting HMRC

Make sure y0u have the following info before you telephone HMRC

  • your personal details – such as your full name, address, date of birth and National Insurance number
  • details of each of your employers – their PAYE scheme reference number, which should be shown on your payslip, or ask your employer for it
  • estimates of your earnings and pensions from each source for the current tax year

Make sure you keep a note, in a safe place for future reference, of

  • the date and time of the phone call
  • the name of the adviser you spoke to and
  • what was said by both you and the HMRC adviser

HMRC may already have everything they need to check your position but you may need to send in more information – if so, HMRC will let you know what paperwork you should supply.

Once HMRC process your information it might be necessary to issue you with a new tax code, meaning any refund will be added to your wages and the amount will generally be paid automatically through the payroll. This will result in a lower tax deduction or a tax refund through PAYE.

How do I claim a refund after the end of the tax year and for previous tax years?

If you have paid too much tax through your employment and the end of the tax year in which you overpaid tax has already passed (and you have not received a P800), you can make a claim for a refund. You can do this online, through your Personal Tax Account (accessed through GOV.UK), or by writing to HMRC.

If you write to HMRC, mark the top of your letter clearly with ‘repayment claim’ so that HMRC can make sure it gets to the right department.

To write to HMRC, use the address on GOV.UK.

Your letter should include the following

  • give your full personal details – your name, address and National Insurance number
  • include as much information as possible about your employment, for example, PAYE reference numbers, how much you were paid and how much tax was deducted
  • enclose copies of P60s and P45s if you have them – keep the originals
  • say why you think you are due a repayment
  • say how you would like to receive any repayment
  • be signed and dated in ink.

Keep a copy of your letter and any enclosures and ask the Post Office for a proof of posting in case of later query.

In most cases you can get back the tax you have overpaid, as long as you claim on time. You have up to four years to make a claim.

Remember, even if you only want HMRC to look at one particular tax year, HMRC may take the opportunity to look over the four ‘open’ tax years. Therefore, you should review your position for all four tax years before contacting HMRC.