How PIP back pay works
PIP starts from the date your claim began, not the date of the decision. Because decisions often take several months, your first payment is usually a lump sum covering every week since you claimed. The same applies when a mandatory reconsideration or tribunal changes the award.
How this is calculated
Back pay = (days from claim start to first regular payment ÷ 7) × weekly PIP
Weekly PIP is the daily living rate plus the mobility rate you were awarded. A part-week counts as a fraction of a week. If you already got PIP at a lower rate for some of the time, the back pay is the difference between the two rates, so work out both and take one from the other.
Worked example
Priya rang to claim PIP on 3 June 2026. The decision arrived in October, awarding the enhanced daily living rate and no mobility. Regular payments started on 21 October 2026, 140 days (20 weeks) after the claim. Back pay is 20 × £114.60 = £2292.00.
Common questions
Is PIP backdated to the date I claimed?
Yes. PIP is paid from the date your claim started, which is usually the day you phoned the DWP or sent the claim form (PIP1). If the decision takes months, the first payment includes everything owed since then.
Do I get back pay if I win at mandatory reconsideration or tribunal?
Yes. If the DWP changes its decision at mandatory reconsideration, or a tribunal awards PIP or a higher rate, the award usually goes back to the date of the original decision or claim. The back pay is normally paid within a few weeks of the DWP getting the tribunal decision.
Will the back pay affect my other benefits?
PIP arrears are ignored as capital for 52 weeks for Universal Credit, Pension Credit and Housing Benefit, so a large back payment should not push you over the savings limit during that time. Tell the office that pays your other benefits about the award, because PIP can increase them too.
Is the back pay worked out at the old or new rates?
At the rate that applied for each week. Weeks before 6 April 2026 use the 2025/26 rates (for example £110.40 for enhanced daily living), and weeks after use the 2026/27 rates. This calculator uses 2026/27 rates for every week, so it slightly overestimates back pay that covers weeks before April 2026.