How your tax credits are worked out

Tax credits are complicated and it can be difficult to understand your award. It is still important to check all your award notices carefully and make sure HMRC have all your correct details, including your income for the tax years they are using. You should also check that the money you are paid matches the amounts HMRC say they are due to pay you.

First of all, HMRC works out your maximum tax credits based just on your circumstances and not your income.

Maximum tax credits

Child Tax Credit and Working Tax Credit elements are added together if you are eligible for both. The elements are:

There’s information on our website about the rates of the tax credit elements.  If there are changes to your circumstances and this affects your tax credit elements, you should let HMRC know.

If you are on Income Support, income-related Employment and Support Allowance, income-based Jobseeker’s Allowance or Pension Credit, you will get the maximum Child Tax Credit for your circumstances.

Reduction of your tax credits because of your income

If you are not on any of these benefits, your tax credits depend on your income. Your initial award is always based on your income in the previous tax year, but it can be finalised or revised based on the current tax year, depending on what has happened to your income. If you are eligible for Child Tax Credit only, you can have income of up to £16,385 (2020/21) before the maximum award is reduced.  If you are eligible for (but not necessarily receiving) Working Tax Credit, on its own or with Child Tax Credit, the award starts being reduced once your income is more than £6,530 per year (2020/21). Your income always include the income of a partner you live with. These income thresholds were different in previous tax years.

If you earn above the threshold that applies to you, you lose 41p of Tax Credits for every £1, so someone who is eligible for Working Tax Credit and had income of £6,531 in the tax year on which their award was based, would get their maximum award less 41p. When your tax credits are reduced, you lose the main elements of Working Tax Credit first, then the childcare element of Working Tax Credit, and finally the child and disabled child elements of Child Tax Credit if applicable. Your tax credits carry on being reduced by all your income over £6,530 or £16,385, so families on relatively low incomes may still end up with a nil award of tax credits. How high your income can be before you lose all your tax credits depends on the elements which apply to you. There is no one cut-off point.

You can also use the any of the benefits calculators to check your entitlement, but remember this is likely to vary from what you actually get as HMRC try to pay you what you are entitled to over the tax year.

The tax credit system works out an award which covers a period of up to a year long. You will normally be paid every four weeks or every week. The Tax Credit Office spreads out your award over what is left of the tax year. This means that you may not be paid the same every time.

Changes to your income

If your income goes up, compared to the previous tax year, or compared to an estimate you have already given HMRC, it is very important to tell HMRC to avoid being overpaid. If it goes down, you can give HMRC an estimate, but you will only get more tax credits if you expect to earn at least £2,500 less than the previous tax year. You should also be really careful not to give too low an estimate, otherwise you will be overpaid. It’s a good idea to keep checking your estimate during the year, and let HMRC know immediately if you realise you’re going to earn more than you expected.

Finalisation and renewals process

At the end of the tax year your tax credit claim is finalised. It is important to respond to any requests for information you receive in order to make sure you are not overpaid. Usually this process also forms your claim for tax credits for the new tax year.

Tax credits and other benefits

Remember if the rate of your tax credits changes for any reason, they count as income for other benefits, for example, Housing Benefit. So it is important to tell the local authority (council) about changes in your tax credits.

If you are moving to Universal Credit (UC), your tax credit award stops the day before your UC starts. You will get a letter from HMRC asking you to finalise your tax credit award based on your circumstances and income for the part of the tax year up until your UC award starts.


If you have further questions and would like to contact our advice team please use our advice contact form below or call us.

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