Last Updated: 12 October 2026
Millions of UK pensioners could receive Income Tax refunds following a historical HMRC calculation error that caused incorrect State Pension figures to appear in tax assessments.
In a major update issued in September 2026, HM Revenue & Customs (HMRC) confirmed that approximately 3.2 million people are expected to receive repayments totalling £19.3 million.
The problem dates back to a change introduced in HMRC’s PAYE systems in 2010. Certain tax calculations incorrectly treated pensioners as receiving 52 weeks of State Pension at the newly increased annual rate, rather than recognising one week at the previous rate and 51 weeks at the new rate.
Although the discrepancy was generally small for an individual taxpayer, the number of potentially affected people made it a significant administrative problem.
HMRC has now corrected the relevant PAYE and Simple Assessment systems and announced plans to address historical overpayments automatically.
However, not every State Pension recipient qualifies for compensation, and the amount refunded will depend on individual tax circumstances.
This updated guide examines the latest HMRC announcement, how the error occurred, who may receive a refund and what pensioners should know about their tax position in 2026/27.
What Is the Latest HMRC Pensioner Income Tax Error Update in 2026?
The latest major development came on 3 September 2026, when HMRC Chief Executive John-Paul Marks wrote to the House of Commons Public Accounts Committee explaining how the department intended to resolve the problem.
The letter confirmed that HMRC had implemented a system correction on 25 August 2026 to prevent the same State Pension calculation error from affecting future PAYE annual reconciliations and Simple Assessment calculations.
HMRC also committed to reviewing historical cases dating back to the 2020/21 tax year.
Most importantly, it confirmed that eligible taxpayers covered by the retrospective programme would not have to submit individual refund claims.
HMRC Pension Tax Error: Key Figures for October 2026
| Key information | Latest confirmed position |
|---|---|
| Estimated people receiving refunds | Approximately 3.2 million |
| Estimated total repayments | £19.3 million |
| Date of PAYE and Simple Assessment system correction | 25 August 2026 |
| Years covered by automatic historical review | 2020/21 onwards |
| Expected repayment period | Mainly during 2026/27 |
| Individual refund application | Not required for identified cases |
| Cases before 2020/21 | Individual review possible with evidence |
Source: HMRC Chief Executive’s correspondence to Parliament, 3 September 2026.
The announcement represents an important change from earlier discussions about whether pensioners would have to discover and challenge minor tax discrepancies themselves.
HMRC now intends to identify and correct eligible cases using information already held in its systems.
Nevertheless, the £19.3 million remains an estimated total for the correction programme. It should not be presented as money already paid to every affected customer.
What Caused the HMRC State Pension Income Tax Error?
The problem arose because taxable State Pension income was not always calculated using the correct weekly pension rates.
State Pension is taxable income, but the Department for Work and Pensions (DWP) normally pays it without deducting Income Tax.
Instead, HMRC considers State Pension income alongside other taxable earnings or pension payments when determining a person’s tax liability.
Why Did HMRC Use 52 Weeks Instead of 51 Weeks?
State Pension rates generally increase in April, but the dates on which different weekly rates apply do not align exactly with the tax year.
For most pensioners receiving a full year’s entitlement, HMRC explained that the correct taxable amount should be calculated using:
- One week at the previous tax year’s pension rate.
- Fifty-one weeks at the new tax year’s rate.
However, some HMRC systems calculated the amount using 52 weeks at the new, higher rate.
For the 2025/26 tax year, the full New State Pension increased from £221.20 to £230.25 per week.
The correct calculation was:
(1 × £221.20) + (51 × £230.25) = £11,963.95
The incorrect calculation was:
52 × £230.25 = £11,973.00
This produced a difference of £9.05.
For someone whose additional taxable income was subject to the 20% basic Income Tax rate, the discrepancy could create an illustrative tax difference of £1.81.
The error was therefore not caused by an incorrect pension increase or an underpayment by the DWP. It concerned how HMRC recorded taxable entitlement.
Readers interested in how annual pension increases are calculated can explore our explanation of the State Pension Triple Lock.
How Many Pensioners Were Affected by HMRC’s Tax Calculation Error?
The number of affected taxpayers requires careful interpretation because several different figures have appeared in reports about the issue.
The original article referred to approximately 8.7 million pensioners. However, that figure should not be presented as the confirmed number of people who were overcharged by this particular error.
HMRC’s detailed July 2026 analysis identified different groups of taxpayers depending on how their Income Tax was calculated.
For 2024/25, approximately 1.4 million PAYE pensioners were estimated to have paid too much Income Tax because of the problem.
HMRC also identified up to 955,000 Self Assessment cases and around 760,000 Simple Assessment cases where an incorrect pension figure may have produced an overpayment.
These last two estimates were upper limits, rather than confirmed counts of actual overpayments.
Original Research: How the Number of Affected PAYE Pensioners Increased
HMRC’s historical figures offer an opportunity to examine how the number of affected pensioners changed between tax years.
| Tax year | Estimated affected PAYE pensioners | Total State Pension population |
|---|---|---|
| 2021/22 | 720,000 | 12.7 million |
| 2022/23 | 762,000 | 12.9 million |
| 2023/24 | 1,167,000 | 13.1 million |
| 2024/25 | 1,409,000 | 13.3 million |
Source: HMRC correspondence dated 1 July 2026, historical data annex.
Our analysis shows that the estimated annual number of affected PAYE pensioners increased by approximately 95.7% between 2021/22 and 2024/25.
The calculation is:
(1,409,000 − 720,000) ÷ 720,000 × 100 = 95.7%
This is a substantial increase in the annual number of people identified through HMRC’s analysis.
However, it does not mean that the financial loss per pensioner increased by 95.7%.
Nor does it establish how many unique individuals were affected across all four tax years, since the same pensioner could appear in multiple annual calculations.
The findings illustrate why even relatively small administrative errors can become significant when they affect a large population over several years.
How Much Could Pensioners Receive in HMRC Tax Refunds?
The amount an individual receives depends on their State Pension entitlement, tax rate, tax history and whether the incorrect figures actually changed the tax collected.
HMRC’s September 2026 estimate provides a useful starting point.
The department expects approximately £19.3 million in repayments to around 3.2 million customers.
Dividing these figures produces an estimated average of:
£19,300,000 ÷ 3,200,000 = £6.03
This is an original calculation based on HMRC’s rounded estimates. It does not represent a fixed repayment amount.
Some eligible pensioners may receive more because the correction covers multiple years, while others could receive smaller amounts.
Original Analysis: The Potential Tax Difference by Year
The following figures show the difference created by using 52 weeks at the new rate rather than the correct entitlement calculation for the full New State Pension.
| Tax year | Pension income discrepancy | Illustrative tax difference at 20% |
|---|---|---|
| 2020/21 | £6.60 | £1.32 |
| 2021/22 | £4.40 | £0.88 |
| 2022/23 | £5.55 | £1.11 |
| 2023/24 | £18.70 | £3.74 |
| 2024/25 | £17.35 | £3.47 |
| 2025/26 | £9.05 | £1.81 |
| Illustrative total | £61.65 | £12.33 |
Source: HMRC historical analysis published in July 2026. These figures are illustrations, not confirmed individual refunds.
The table reveals two important findings.
First, the possible financial impact was not equal every year. The larger State Pension increases in 2023/24 and 2024/25 created larger differences between the correct and incorrect calculations.
Second, a pensioner who experienced the discrepancy over several years could have a larger cumulative amount than the annual overpayment figures suggest.
For example, £12.33 is the theoretical combined basic-rate tax difference across these six tax years for someone entitled to the full New State Pension throughout.
That figure assumes each discrepancy translated into additional tax and does not account for HMRC’s administrative tolerances, adjustments or individual circumstances.
Therefore, £12.33 should not be advertised as a standard repayment entitlement.
Why Did Some Pensioners Pay More Tax While Others Did Not?
The calculation error did not necessarily lead to an overpayment in every case.
HMRC’s July correspondence explained that many small discrepancies fell within established administrative tolerances.
These tolerances allow certain very small tax balances to be handled without automatically collecting or repaying them.
Consequently, an incorrect pension figure might have appeared in someone’s records without changing the amount of Income Tax ultimately collected.
The impact also depended on the person’s marginal tax rate.
A pensioner whose entire taxable income remained below their Personal Allowance might not have been charged additional tax despite the incorrect pension figure.
Someone receiving a workplace pension, employment income or other taxable payments could have been affected differently.
This is why the distinction between an incorrect taxable-income figure and an actual Income Tax overpayment is essential.
Who Is Eligible for the HMRC Pension Tax Refund?
Eligibility is determined by whether the historical calculation error caused the individual to pay too much Income Tax.
Several categories of pensioners may be relevant.
Pensioners Receiving State Pension and Workplace Pension Income
Many retirees receive a combination of State Pension and workplace pension income.
Because State Pension is normally paid without tax deductions, HMRC may collect the Income Tax owed on it through the PAYE code applied to another pension.
An incorrect State Pension amount could result in too much taxable income being included in the calculation.
The same principle may apply to pensioners who continue working after reaching State Pension age.
The distinction between the different types of pension is important because workplace pension payments normally have PAYE deductions while State Pension payments do not.
Pensioners Completing Self Assessment Tax Returns
Some pensioners must submit Self Assessment tax returns because they have additional income or other relevant tax circumstances.
HMRC confirmed that incorrect State Pension figures had been included in some information automatically entered into its online Self Assessment service.
However, not every Self Assessment customer was affected.
People using third-party software might not have received the same pre-populated figures, while others could have manually corrected their pension information before submitting their returns.
HMRC said in September that it expected to correct 2025/26 pre-populated pension figures and address relevant returns already submitted.
Pensioners Receiving Simple Assessment Tax Bills
Simple Assessment allows HMRC to calculate an Income Tax liability without requiring a full Self Assessment return.
Some pensioners receive these calculations when they owe Income Tax that cannot be collected through PAYE.
HMRC identified Simple Assessment as another part of the tax system affected by the historical pension calculation problem.
The department’s August correction is intended to ensure that future relevant calculations use accurate State Pension entitlement figures.
Will HMRC Automatically Refund Pensioners in 2026?
Yes, for eligible cases identified under the retrospective correction programme covering tax years from 2020/21 onwards, HMRC has stated that taxpayers will not need to make individual refund claims.
This means pensioners should not generally have to calculate several years of overpayments independently to become part of the programme.
However, the way HMRC provides the money may vary.
How Could Pensioners Receive Their Repayments?
HMRC has outlined three main approaches.
| Repayment method | How it may work |
|---|---|
| PAYE tax code adjustment | HMRC adjusts tax collected through another taxable pension or employment income |
| Self Assessment account credit | A correction is credited to the taxpayer’s Self Assessment account |
| Other payment methods | A payable order or another suitable repayment method may be used |
Not every affected pensioner should expect a separate bank transfer or cheque.
Some repayments may be reflected in tax-code adjustments or account balances.
Pensioners should therefore review official correspondence carefully to understand how any correction has been applied.
When Will the Refunds Be Completed?
HMRC expects the majority of corrections and repayments to take place during the 2026/27 financial year.
That period ends on 5 April 2027.
As of 12 October 2026, the department’s September correspondence provides the expected timetable but does not establish that all 3.2 million repayments have already been completed.
There is also no universal confirmed payment date for every recipient.
What About Pensioners Overcharged Before 2020?
The automatic correction programme covers tax years beginning with 2020/21.
However, HMRC acknowledged that the underlying system problem originated much earlier.
According to its July 2026 correspondence, incorrect figures may have affected:
- PAYE reconciliations from 2010/11.
- Self Assessment pre-populated information from 2015/16.
- Simple Assessment calculations from 2016/17.
The department explained that available records allow it to identify and correct cases reliably from 2020/21 onwards.
For earlier years, individuals who believe they were affected can request a review with appropriate supporting evidence.
These cases will be assessed individually.
There is no guarantee that every historical request will lead to repayment.
Pensioners investigating an older discrepancy should retain any relevant pension entitlement letters, PAYE tax notices, Self Assessment returns and previous HMRC calculations.
How Can Pensioners Check Whether They Paid Too Much Income Tax?
Although HMRC is handling the retrospective correction exercise automatically, checking personal tax records can still be worthwhile.
Pensioners can use their HMRC online account to examine the income information held by the department and review relevant tax calculations.
Check the Correct State Pension Entitlement
The first step is to establish the appropriate State Pension amount for the tax year concerned.
A common mistake is to add together State Pension payments deposited into a bank account between 6 April and 5 April.
That total does not always equal taxable entitlement because State Pension is normally paid in arrears.
Instead, pensioners should use their entitlement dates and applicable weekly pension rates.
Review PAYE Tax Codes and P800 Calculations
A pensioner receiving workplace pension income or continuing in employment may have tax collected through PAYE.
Reviewing tax-code notices and P800 calculations can help identify unexpected income figures.
However, a pensioner should not assume that every difference in the amount shown represents an overpayment.
Tax codes can also include adjustments for other income, allowances or previous tax liabilities.
For a wider explanation of how PAYE software processes deductions, London Business Mag has published a guide to HMRC Basic PAYE Tools.
Check Whether the Problem Is a Different State Pension Error
The 51-week versus 52-week tax issue should not be confused with errors involving State Pension forecasts or National Insurance records.
Those issues concern the calculation of pension entitlement itself, rather than the Income Tax charged on an existing entitlement.
Readers can find the distinction in our separate investigation into the HMRC State Pension forecast error.
Understanding which issue applies is important before approaching HMRC or the DWP.
How Does the 2026/27 State Pension Affect Income Tax?
The historical tax calculation error has become especially relevant because State Pension income is approaching the standard Income Tax Personal Allowance.
From April 2026, the full New State Pension increased to £241.30 per week, while the full Basic State Pension increased to £184.90.
The standard Personal Allowance remains £12,570 for the 2026/27 tax year.
This creates a narrow margin between the full New State Pension and the tax-free threshold.
For more background on the April rate changes, see our 2026 State Pension increase guide.
Original Calculation: New State Pension Versus Basic State Pension in 2026/27
The following comparison applies HMRC’s correct annual entitlement method to both full pension rates.
| Calculation | Full New State Pension | Full Basic State Pension |
|---|---|---|
| Previous weekly rate | £230.25 | £176.45 |
| New weekly rate | £241.30 | £184.90 |
| 52 weeks at new rate | £12,547.60 | £9,614.80 |
| Correct annual entitlement: one old week plus 51 new weeks | £12,536.55 | £9,606.35 |
| Difference between methods | £11.05 | £8.45 |
| Illustrative tax difference at 20% | £2.21 | £1.69 |
London Business Mag calculation using official 2025/26 and 2026/27 State Pension rates. This is a comparison of calculation methods, not a claim that HMRC has continued making the error after August 2026.
The results demonstrate that the tax calculation issue could produce different amounts depending on which State Pension system a person receives.
They also show why accurate pension entitlement information remains important even when the numerical difference appears small.
Individual pension amounts can differ substantially from the full headline rates, particularly for people with additional State Pension entitlements or incomplete contribution records.
Could the Full New State Pension Become Taxable in 2026?
For a person receiving the full New State Pension throughout 2026/27, the correctly calculated entitlement in this example is £12,536.55.
The standard Personal Allowance is £12,570.
This leaves a difference of:
£12,570 − £12,536.55 = £33.45
Therefore, a pensioner receiving only this amount, with the full standard Personal Allowance available and no other taxable income, would remain below the Income Tax threshold.
However, an additional taxable private pension could create a liability.
Example: A Pensioner Receiving £500 of Private Pension Income
Consider a pensioner with the following income:
| Income or calculation | Annual amount |
|---|---|
| Taxable New State Pension entitlement | £12,536.55 |
| Additional private pension income | £500.00 |
| Total taxable income before allowances | £13,036.55 |
| Standard Personal Allowance | £12,570.00 |
| Income above the allowance | £466.55 |
| Illustrative Income Tax at 20% | £93.31 |
The calculation assumes the taxpayer pays the applicable 20% rate on this income and has no other relevant reliefs or adjustments.
This example illustrates how someone can begin paying Income Tax despite receiving only a relatively small additional private pension.
The position can be different for Scottish taxpayers, whose non-savings income is subject to Scottish Income Tax rates and bands.
Savings income may also qualify for separate allowances or reliefs, so it should not automatically be treated in the same way as additional private pension income.
Readers concerned about the interaction between pension income and frozen thresholds can read our State Pension tax warning.
Why Does the HMRC Error Matter Beyond Small Refunds?
HMRC’s correction programme is important not simply because of the money being repaid, but because of what the problem reveals about the administration of pension taxation.
The Financial Impact Can Be Small but Widespread
A tax discrepancy of £1 or £2 may appear minor when considered individually.
However, millions of affected records can collectively produce substantial repayment obligations.
The estimated £19.3 million correction programme demonstrates the cumulative financial consequences of a calculation issue that remained embedded within administrative processes for years.
Pension Tax Calculations Are Difficult to Check Independently
State Pension is paid differently from employment income.
Recipients normally do not receive a traditional annual P60 for their State Pension from the DWP, making it less straightforward to reconcile pension entitlement with HMRC calculations.
The issue is particularly challenging when the correct annual taxable amount does not match the simple total of bank payments received during the tax year.
This creates a strong argument for clearer tax notices, accessible explanations and more effective checks between government departments.
Frozen Tax Thresholds Increase the Importance of Accuracy
The Personal Allowance has remained at £12,570 even as State Pension rates have increased.
As a result, more pensioners can become liable for Income Tax when their retirement income rises.
This effect, commonly known as fiscal drag, makes accurate calculations especially important for people whose income is close to the threshold.
However, the historical calculation error and the decision to freeze tax allowances are separate issues.
The HMRC error involved the administration of taxable State Pension figures. Fiscal drag concerns the relationship between increasing income and unchanged tax thresholds.
Both can affect pensioners, but they should not be confused.
What Should Pensioners Do Now?
Pensioners who may be covered by the automatic correction programme do not generally need to submit a special repayment claim.
However, they should continue to review official tax correspondence and make sure their personal details are accurate.
For people who believe the error occurred before 2020/21, collecting historical pension and tax documents may be necessary before requesting an individual review.
Anyone receiving a current tax bill should follow the relevant HMRC procedure if they believe it is incorrect. They should not ignore a payment deadline solely because HMRC has announced a historical correction programme.
Pensioners should also remain cautious about fraudulent messages offering immediate pension tax refunds.
Unexpected emails, texts or calls asking for bank details or payments to release a refund should be treated with suspicion.
HMRC’s wider work on pensioner taxation includes other measures that are not part of this calculation error. For example, the recovery of Winter Fuel Payments from certain higher-income pensioners operates under separate rules, explained in our Winter Fuel Payment clawback 2026 guide.
Conclusion
The HMRC pensioner income tax error is an example of how a relatively small administrative miscalculation can create financial consequences for millions of taxpayers.
The latest September 2026 announcement marks an important stage in resolving the issue.
HMRC has confirmed a correction to its relevant PAYE and Simple Assessment systems and expects approximately 3.2 million customers to receive repayments totalling around £19.3 million.
The department also intends to correct eligible historical cases from 2020/21 without requiring affected taxpayers to submit individual claims.
For pensioners, the most important distinction is between an incorrect State Pension figure and an actual tax overpayment.
Not every person whose pension information was inaccurate will necessarily be owed money.
With the full New State Pension approaching the standard Income Tax Personal Allowance in 2026/27, accurate pension tax administration is becoming increasingly important.
Pensioners should check their records, retain relevant documentation and rely on official HMRC correspondence when determining whether a correction or repayment applies to them.
Research Methodology: This article was updated on 12 October 2026 using HMRC’s parliamentary correspondence dated 1 July and 3 September 2026, official State Pension rates and published Income Tax allowances. Historical PAYE comparisons, percentage changes and illustrative refund calculations were independently derived from those figures. Estimated outcomes are distinguished from completed repayments, and no individual HMRC tax records were examined.
Frequently Asked Questions
Has HMRC Fixed the Pensioner Income Tax Error?
HMRC confirmed that it implemented the relevant PAYE annual reconciliation and Simple Assessment system correction on 25 August 2026. It also outlined measures to correct Self Assessment information and historical tax positions.
How Many Pensioners Will Receive HMRC Tax Refunds?
HMRC estimates that approximately 3.2 million customers will receive repayments through its historical correction exercise covering tax years from 2020/21.
How Much Is the Average Pensioner Tax Refund?
HMRC’s estimated £19.3 million total divided by approximately 3.2 million recipients produces a calculated average of around £6.03. Actual refunds will vary.
Do Pensioners Need to Claim the Refund?
HMRC says that eligible cases identified under its retrospective correction programme will be handled without requiring individual claims. Requests involving earlier years may require supporting evidence.
When Will HMRC Pay the Pension Tax Refunds?
HMRC expects the majority of corrections and repayments to be completed during the 2026/27 financial year. Individual payment dates have not been confirmed for everyone.
Does the Error Affect Every State Pension Recipient?
No. The problem affected certain tax calculations. Whether it caused additional tax to be paid depends on the individual’s circumstances, tax rate and applicable administrative adjustments.
Is the State Pension Taxable in 2026/27?
Yes. State Pension is taxable income, but Income Tax depends on the person’s total taxable income and available allowances. Someone whose only taxable income is the full New State Pension may remain below the standard Personal Allowance in 2026/27.
Can Pensioners Get Refunds for Years Before 2020?
HMRC says individuals who believe they were affected before 2020/21 can request a review with suitable evidence. Such requests will be considered individually and repayment is not guaranteed.