# UK Self Assessment Checklist — 2025/26 Tax Year

**Filing deadline (online): 31 January 2027**
**Registration deadline (year of starting): 5 October 2026**

## Before you start

- [ ] Government Gateway ID (create at gov.uk if new)
- [ ] Unique Taxpayer Reference (UTR) — 10 digits from HMRC
- [ ] National Insurance number
- [ ] Bank account for tax payments

## Income records to gather

- [ ] All invoices sent between 6 April 2025 and 5 April 2026
- [ ] Bank statements matching those invoices (payments received)
- [ ] Platform payout statements (PayPal, Stripe, Fiverr, Upwork, Etsy, etc.)
- [ ] P60 or P45 from any employment during the tax year
- [ ] Dividend vouchers from any Ltd companies you hold shares in
- [ ] Interest statements from banks (untaxed interest)
- [ ] Rental income records (if applicable)
- [ ] Foreign income records (if applicable)

## Expense records to gather

- [ ] All receipts for the tax year (business only)
- [ ] Home office calculation: flat rate (£312/year) OR apportioned actual costs
- [ ] Business mileage log (date, purpose, miles)
- [ ] Software / subscription invoices (business use only)
- [ ] Insurance premiums (business insurance)
- [ ] Professional fees (accountant, professional body subs)
- [ ] Equipment invoices for capital allowances (AIA up to £1m)

## Reliefs to check (commonly missed)

- [ ] Personal pension contributions (higher-rate top-up claimed on SA)
- [ ] Gift Aid donations (higher-rate top-up)
- [ ] Marriage Allowance transfer (£252 if applicable)
- [ ] Trading Allowance (£1,000) — use if better than actual expenses
- [ ] Loss carry-back (if loss-making this year)
- [ ] Marriage Allowance from lower-earning spouse

## After filing

- [ ] Save the submission receipt PDF
- [ ] Diary the tax bill payment date (31 January)
- [ ] Diary payments on account if bill > £1,000 (31 January + 31 July)
- [ ] Set up tax-savings account for next year (25-30% of income)
- [ ] Update Bookkeeping records for the new tax year

## Sources referenced

- HMRC — Self Assessment tax returns: https://www.gov.uk/self-assessment-tax-returns
- HMRC — Register for Self Assessment: https://www.gov.uk/register-for-self-assessment
- HMRC — Trading Allowance: https://www.gov.uk/guidance/tax-free-allowances-on-property-and-trading-income
- HMRC — Pension tax relief: https://www.gov.uk/tax-on-your-private-pension/pension-tax-relief

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*This checklist is general guidance based on UK rules for the 2025/26 tax year. Not personal tax advice. For your specific situation, consult a qualified accountant or HMRC.*

*Downloaded from FreelanceToolkit UK — https://freelancetoolkituk.co.uk/self-assessment-checklist*