HMRC says a tax calculation error may have caused millions of state pensioners to pay too much income tax. Reports cite that up to 8.7 million pensioners were affected last year, with the overcharge estimated at around £5 per person on average. HMRC says the difference stems from how the income tax liability is calculated across pension payment periods when the state pension rate changes, and that its system used 52 weeks of state pension paid at the new rate rather than the approach intended to reflect the tax year timeline. HMRC has apologised to those affected and says it is working to correct the issue, aiming to resolve it later this summer. The department says it is assessing how many people were impacted and is not currently issuing automatic refunds. Instead, HMRC says individuals can contact it to have incorrect figures amended and receive any refund. Multiple outlets report concerns that the error was not detected for about 10 months, with political criticism about how quickly it was identified and escalated. Estimates in some coverage suggest HMRC collected an additional total of tens of millions of pounds, but HMRC is focused on identifying affected individuals and fixing the calculation.