SA100 tax return: the paper Self Assessment form

The paper SA100 for 2025 to 2026 must reach HMRC by 31 October 2026. Check the supplementary pages you need, sign it, and post it to the right address.

Official HMRC form

Get the SA100 tax return (2026) on GOV.UK

Download the paper return, HMRC's 'How to fill in your tax return' notes and the supplementary pages.

Download the SA100 and notes →

Paper SA100, online return or SA200?

Online return

Due by 31 January 2027. GOV.UK says it gives you an extra 3 months over paper and you can save your details and finish later.

Paper SA100

HMRC must receive it by 31 October 2026. Download it from GOV.UK or call HMRC for a copy, and post it with any supplementary pages.

Short return SA200

Only fill this in if HMRC sends it to you. It cannot be downloaded.

How to complete and send a paper SA100

1

Gather your records

HMRC's notes list your P60, P11D or P45, payslips or P2 coding notice, business records if you work for yourself, bank and building society statements, dividend details and pension contribution certificates.
2

Answer page TR 2 and get your supplementary pages

Each 'Yes' on page TR 2 means you must also fill in and send the matching supplementary pages, or HMRC treats the return as incomplete and sends it back.
3

Fill in the SA100 sections

Work through personal details, income, tax reliefs, loans and charges, then 'Finishing your tax return'. Enter figures carefully.
4

Sign, date and post it

Sign and date the declaration yourself, then post it to BX9 1AS if you live in the UK, or to the Newcastle address if you live abroad.

SA100 section by section

These follow HMRC's SA150 notes for the SA100 (2026). Read the first 2 pages of the return before you start.

Page TR 2 — what makes up your return: Tick 'Yes' for each kind of income or gain you had. Each one needs its supplementary pages, such as SA102 Employment (one per job, directorship or office), SA103S or SA103F Self-employment, SA105 UK property, SA106 Foreign, SA108 Capital gains or SA109 Residence.
Your personal details: Give your date of birth (HMRC says you may not get all your allowances without it). If your address is different or missing, write it in or under the 'Issue address' box and give the date you moved.
Income: UK interest and dividends; UK pensions, annuities and other state benefits received; and other UK income not included on supplementary pages. Leave out ISA interest, and only enter your share of any joint income.
Tax reliefs: Payments into registered pension schemes and overseas pension schemes, charitable giving, and Blind Person's Allowance.
Loans, charges and Marriage Allowance: Student Loan and Postgraduate Loan repayments, the High Income Child Benefit Charge, the Winter Fuel Payment and Pension Age Winter Heating Payment charge, and Marriage Allowance.
Finishing your tax return: Tax refunded or set off, what happens if you have not paid enough tax (including collection through your tax code), what to do if you have paid too much, and 'Any other information' in box 19.
Signing your form and sending it back: Box 20 is only for provisional figures you will replace with final ones; explain them in 'Any other information'. Boxes 23 to 26 are for executors, court-appointed people and attorneys. Sign and date the declaration at box 22.

Mistakes HMRC's notes warn about

Ticking 'Yes' on page TR 2 but not sending the supplementary pages: HMRC treats the return as incomplete and sends it back.
Forgetting to sign and date the form yourself: HMRC cannot accept it and returns it.
Correcting a mistake by overwriting: strike through the error and put the correct details next to the box.
Leaving out your date of birth, which can cost you allowances.
Sending receipts, accounts or letters with the return when HMRC has not asked for them.
Assuming someone else is responsible because they filled it in: you remain responsible and must sign.

Paper filers get their tax calculation from HMRC

If HMRC receives your paper return by the deadline, it works out your tax and tells you before 31 January 2027, with a tax calculation that also says whether you need payments on account. Online filers can print the same calculation as an SA302.

Frequently asked questions

What is the SA100?

SA100 is HMRC's main Self Assessment tax return. The paper SA100 (2026) covers the 2025 to 2026 tax year. Other income, such as employment, self-employment, property, foreign income or capital gains, goes on supplementary pages sent with it.

What is the SA100 paper deadline?

HMRC must receive a paper return for the 2025 to 2026 tax year by 11:59pm on 31 October 2026. Online returns are due by 11:59pm on 31 January 2027, and any tax owed must be paid by 31 January 2027.

Where do I send my SA100?

If you live in the UK, post it to Self Assessment, HM Revenue & Customs, BX9 1AS, United Kingdom. If you live outside the UK, post it to HM Revenue & Customs, Benton Park View, Newcastle Upon Tyne, NE98 1ZZ, United Kingdom.

How do I get a paper SA100?

Download the SA100 from GOV.UK or call HMRC and ask for one. Only use the short tax return (SA200) if HMRC sends it to you; it cannot be downloaded.

I missed the paper deadline. What now?

GOV.UK says that if you miss the paper filing deadline, send your tax return online instead to avoid a penalty. The online deadline is 31 January 2027.

Should I file the SA100 online instead?

GOV.UK says filing online gives you an extra 3 months, makes amendments easier, and lets you save your details and finish later. Some returns, such as those for trustees of registered pension schemes, still need a paper form.

Do I send receipts with my SA100?

No. HMRC's notes say not to send receipts, accounts or other paperwork or correspondence with your return unless HMRC asks for them; doing so slows down the return and any repayment.

I registered late. When is my return due?

If you register after 5 October 2026, HMRC sends you a letter or email with a different deadline: 3 months from the date on it. You must still pay the tax you owe by 31 January 2027.

Official sources

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