Overview
- The 4.8% triple lock increase to the state pension applies automatically from April 6, 2026, at the start of the new tax year.
- DWP will notify HMRC of uprated pension amounts, triggering recalculations that can affect both the current tax year and the next.
- For most people taxed through PAYE, HMRC assumes one week at the old pension rate and 51 weeks at the new rate to set the annual figure.
- HMRC says tax codes are predictions of taxable income, so adjustments can result in refunds or extra amounts being collected later.
- A recent case of a refund followed by a code change prompted HMRC to highlight that unaccounted changes during the year can alter how much tax is due, with details viewable in the HMRC app or online account.