Each is half
Each payment on account is half of last year's Income Tax and Class 4 National Insurance, paid through Self Assessment. They are due by 31 January and 31 July.
Free payments on account calculator
If your last Self Assessment bill was £1,000 or more, HMRC usually asks for two payments on account towards the next one, on 31 January and 31 July. Enter last year's bill and see whether you have to make them, how much each is, and what is due when.
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HMRC's rule
Each payment on account is half of last year's Income Tax and Class 4 National Insurance, paid through Self Assessment. They are due by 31 January and 31 July.
You do not have to if last year's bill was under £1,000, or if more than 80% of the tax you owed was taken at source - through your tax code, for example.
If you earned more than the payments covered, the rest is due by 31 January as a balancing payment. If you earned less, you may be able to claim some back, or ask HMRC to reduce the payments.
HMRC's own words: Payments on account. Work out the bill itself with the self-employed tax calculator.
What Stoneledger does
Your tax building month by month, so 31 January and 31 July are never a surprise.