Refund letter · NISPAR1MM
National Insurance refund after State Pension age (NISPAR1MM)
For HMRC's letter inviting you to claim back National Insurance contributions paid after you reached State Pension age. This page sets out what HMRC's own list says about the letter, the ways to claim and what follows, with each source and the date it was checked.
Last reviewed 8 October 2026 · How Tax Letters checks its facts
The short answer
- What this letter is
- HMRC says it may write to you, from 10 July 2026 up to and including 31 March 2027, if its records show that you continued to pay National Insurance contributions after reaching State Pension age, and may invite you to claim a refund. [1]
- What it asks
- HMRC's list says the letter asks you either to complete the form on the back of the letter with your bank details and post it to HMRC, or to contact HMRC using the National Insurance helpline. [1]
- Before you claim
- GOV.UK says you will never get an email, text message, message in an application (for example WhatsApp) or a phone call from HMRC which tells you about a tax rebate or penalty, or asks for your personal or payment information. [2]
- Your options at a glance
- A refund claim, not a bill
Every fact on this page comes from a source listed at the foot of the page, with the date it was last checked. All sources and dates
Is it real, before you claim
This page cannot prove a letter is genuine. HMRC's own list of genuine letters describes this one. HMRC's list says the letter asks you either to complete the form on the back of the letter with your bank details and post it to HMRC, or to contact HMRC using the National Insurance helpline. [1]
GOV.UK says you will never get an email, text message, message in an application (for example WhatsApp) or a phone call from HMRC which tells you about a tax rebate or penalty, or asks for your personal or payment information. For a suspicious letter, GOV.UK says to contact the HMRC team the letter says it is from, for example the Self Assessment team. [2]
HMRC publishes a list of letters it has recently sent, to help you check if a letter you have received from HMRC is genuine. [1]
How to claim, and how the money reaches you
The form on the back of the letter
You can apply using the form on the back of your letter and send it to the address shown at the top of the letter. [3]
The National Insurance helpline
National Insurance enquiries: 0300 200 3500, Monday to Friday, 8am to 6pm. [4]
Online, if your letter has a claim reference number
GOV.UK has an online service to apply for a refund if HMRC has written to you about overpaid National Insurance contributions and your letter includes a claim reference number. You can only use it if a letter from HMRC told you that you may be due a refund. To apply online you need the claim reference number shown on your letter and bank or building society account details, and to check that the Class 2 and Class 3 contributions and National Insurance credits shown in your letter are correct. You can update incorrect information during the application. GOV.UK says that if your letter does not mention Class 2 or Class 3 National Insurance contributions or National Insurance credits, the records HMRC holds show you did not pay or receive them. If there is no claim reference number on your letter, you cannot use the online service. GOV.UK: apply for a refund of National Insurance contributions [3]
HMRC says it will review your National Insurance record and confirm if you are due a refund. HMRC will check your application and write to you with the outcome. GOV.UK says that if you want to see how long it will take to hear back from HMRC, you can check when you can expect a reply from HMRC. GOV.UK: check when you can expect a reply from HMRC GOV.UK says the information in HMRC's reply-time tool is updated weekly. [1] [3] [5]
Regulation 52(4) of the Social Security (Contributions) Regulations 2001 says that when an application is made for the return of a contribution paid in error, the contribution shall be returned. The same regulation sets a minimum amount and one other exception. [6]
If one of these is you
You are still working
Even if you are still working, when you reach State Pension age you usually stop paying National Insurance contributions. You can claim back National Insurance if you have overpaid. If you continue working, GOV.UK says to show your employer proof of your age, such as a birth certificate or passport, to make sure you stop paying National Insurance. [7]
You would rather your employer did not see your passport
If you do not want your employer to see your birth certificate or passport, HMRC can send you a letter to show them instead, confirming that you have reached State Pension age and do not need to pay National Insurance. You need to write to HMRC explaining why. [7]
You have had more than one refund letter
If you have received more than one National Insurance refund letter, GOV.UK says you need to make a separate claim for each one. [3]
Your health or circumstances make this hard
HMRC offers extra support if your health condition or personal circumstances make it difficult to contact HMRC, for example a mental health condition, financial hardship or being treated in hospital. You can authorise a friend, relative or voluntary organisation to talk to HMRC for you and help you fill in forms. [8] [9]
Keep it
Keep this with the letter. Mark what you did:
You can always deal with HMRC directly, free, without any service or adviser. Free help: TaxAid, which says it helps “people who can’t afford to pay for help”, and Citizens Advice. [10] [11]
Sources
Each source is linked, with the date Tax Letters last checked it.
- GOV.UK: Check if a letter you've received from HMRC is genuine (letter NISPAR1MM) (checked 7 Oct 2026)
- GOV.UK: Report scam HMRC messages, calls and social media accounts (checked 7 Oct 2026)
- GOV.UK: Apply for a refund of National Insurance contributions (checked 7 Oct 2026)
- GOV.UK: National Insurance: enquiries (checked 7 Oct 2026)
- GOV.UK: Check when you can expect a reply from HMRC (checked 8 Oct 2026)
- legislation.gov.uk: Social Security (Contributions) Regulations 2001, regulation 52 (checked 8 Oct 2026)
- GOV.UK: National Insurance and tax after State Pension age, stop paying National Insurance (checked 7 Oct 2026)
- GOV.UK: Get help from HMRC if you need extra support (checked 7 Oct 2026)
- GOV.UK: Appoint someone to deal with HMRC on your behalf (checked 7 Oct 2026)
- TaxAid: About us (checked 8 Oct 2026)
- Citizens Advice: About us (checked 7 Oct 2026)