Understanding and checking your tax calculation

If you send a paper tax return, HM Revenue & Customs (HMRC) will usually send you a tax calculation. If you send an online Self Assessment tax return, you can view your calculation online or print it. Your tax calculation is based on the figures you provide in your tax return. If your tax return is wrong you need to correct it or tell HMRC right away, before you get your tax bill.

On this page:

Receiving your tax calculation

HMRC will only send you a paper tax calculation, called form SA302, if:

  • you sent in a paper tax return before 31 October and asked HMRC to work out your tax
  • you made an amendment to a paper tax return
  • you sent in a tax return but HMRC doesn't agree with your tax calculation

If you sent a paper tax return, you can also work out how much tax is due yourself. Follow the link below and download the tax calculation summary, notes and working sheets. If you do your tax return online, your tax calculation is worked out for you and you can see it on screen or print it.

Download the Tax Calculation Summary and notes

Sometimes you may be asked for your tax calculation by a bank or other lender as evidence of your income. You don't have to ask HMRC for a paper copy. If you do an online tax return, you can print off your tax calculation yourself. It may not show the form number - SA302.


Your tax calculation covering letter

A tax calculation sent through the post will have a covering letter. This tells you:

  • the tax year the calculation refers to
  • the total Income Tax due for that tax year - taken from the accompanying calculation pages
  • about any changes HMRC has made to the figures on your tax return
  • about any payments on account you'll need to pay for next year

Find out more about payments on account


If you think your calculation is wrong

It's important to check the figures on your tax calculation. If you think they are wrong, you may be able to put them right by amending your tax return. If not, you'll need to contact HMRC as soon as possible.

HMRC will use the tax calculation figures to create your 'Self Assessment Statement'. This is a statement that you receive later that asks for payment if you owe tax, or tells you that you're due some tax back.

If the figures are wrong you may end up paying too much or too little tax. If you pay too little tax, you may have to pay interest and penalties when the mistake is put right.

Read more about correcting your tax return


Understanding the entries on your tax calculation

There's information below about each entry on your tax calculation.

Income received (before tax was taken off)

This lists all your taxable income for the year - including the gross amounts before tax was deducted for things such as:

  • pay, minus any allowable expenses you can claim
  • any taxable benefits and expenses you received through work
  • profits if you're self-employed or a partner in a business partnership
  • savings interest
  • dividends (the amount shown includes the 10 per cent 'tax credit' - follow the link below if you're not sure what this means)

Tax on UK dividends - learn more

Total income on which tax is due

This is the income you received - explained above - minus any tax-free personal allowances and deductions to which you're entitled.

Income Tax due

In this section you'll see the rate of tax that's been applied to your pay, pensions, profits, investment income etc. Different types of income are taxed at different rates and income above a certain level is taxed at a higher rate of tax.

If you pay higher rate tax, your calculation may show here adjustments to make sure you get the right tax relief for certain payments you've made. For example if you gave to charity using Gift Aid, you'll only have received basic rate tax relief at 20 per cent when you made the gift. The tax calculation will show an adjustment to give you the extra tax relief to which you're entitled.

Income tax rates and tax bands - find out more

Total tax due

This is the total tax due for this tax year after taking into account adjustments such as:

  • tax you've paid through your PAYE (Pay As You Earn) tax code
  • tax deducted from your savings income
  • refunds you've already received for the year

However the 'Total tax due' figure isn't necessarily the amount you'll be asked to pay. This is because it doesn't take into account any payments that you may have already made direct to HMRC, for example payments made by Direct Debit or by cheque. It also doesn't take into account any amounts you may owe for earlier years. The Self Assessment Statement that will follow will tell you exactly how much you owe or are due back.

Other entries on the calculation

Other entries that you may see on your calculation may include:

  • Class 4 National Insurance contributions - if you're self-employed
  • Capital Gains Tax
  • Student Loan repayments

Find out more about Capital Gains Tax

Read about National Insurance contributions

Repaying student loans


Paying what you owe

The tax calculation and any covering letter aren't demands for payment, but they do tell you:

  • the date by which you must pay any tax you still owe
  • about any payments on account you'll need to pay for next year

If you don't receive your Self Assessment Statement before the next payment is due, you'll need to work out how much tax you owe. You can use your tax calculation, together with previous statements .

Better still, if you sign up for Self Assessment Online, you can look up exactly what you owe online instead.

Make sure you pay on time - you'll have to pay interest if you pay late.

Sign up for Self Assessment Online

How to pay Self Assessment

Your Self Assessment Statement - find out more


If your payments on account look too high

Your tax calculation may tell you that you need to make payments on account for the current tax year. These payments are based on the income shown on your last tax return because HMRC assumes your income next year will be similar.

If your income has gone up, you don't need to do anything. The payments on account don't need to change.

If your income has gone down, you may think that your payments on account are too high. In this case, you can use form SA303 to ask HMRC to reduce them. You must make sure you tell HMRC if your income goes back up, otherwise you may have to pay interest on any tax you pay late.

You can also sign up to use Self Assessment Online and reduce your payments on account online instead.

Sign up for Self Assessment Online

Go to form SA303: Claim to reduce payments on account

Telephone or write to HMRC


Managing your tax online

Register for Self Assessment Online, then you can manage your own tax in several ways. For example:

  • if you sent your return online, you can print your own tax calculation
  • you can look up what you owe using the 'View Account' option - you can do this even if you've sent your tax return on paper
  • if your income has gone down, you can ask to reduce your payments on account


More useful links

Download 'How to fill in your tax return' (PDF 225K)

Download 'How to fill in your short tax return' (PDF 160K)