Taxes Management Act 1970 section 59B

Payment of income tax and capital gains tax: assessments other than simple assessments

Section 59B sets out how the balancing payment or repayment of income tax and capital gains tax is calculated and when it falls due, covering self-assessment returns, amended assessments, and other types of assessment.

• The balancing payment (or repayment) is the difference between the tax shown in a self-assessment and the total of payments on account, PAYE deductions, and other tax deducted at source, with adjustments for cross-year PAYE amounts
• The balance is normally due by 31 January following the tax year, but where HMRC issued the return notice late (after 31 October), the taxpayer has three months from the date of that notice to pay
• Repayments can be withheld while HMRC is enquiring into a return, although the officer may make provisional repayments before the enquiry is completed
• Tax arising from amendments, corrections, or non-self-assessment charges has its own payment deadlines — either as specified in Schedule 3ZA or 30 days after the notice of assessment is issued