Filing your Self-Assessment doesn't have to be a New Year scramble. Here's the 7-step checklist we send to every LedgerlyPro user in early January.
1. Confirm you actually need to file
You generally need to file a Self-Assessment if you earned more than £1,000 in self-employed income, received untaxed dividends above £500, or had foreign income.
2. Gather your income evidence
- Invoices issued in the tax year
- Platform payout statements (PayPal, Stripe, Patreon)
- P60s from any employment
LedgerlyPro automatically prepares this list for you — open the Tax Estimator and click Export Self-Assessment summary.
3. Collect allowable expenses
The most-missed UK allowable expenses for self-employed people:
| Expense | Rule |
|---|---|
| Home office | Use of home as office — £6/week flat rate or actual costs |
| Mileage | 45p/mile first 10,000 miles, 25p thereafter |
| Phone | Business proportion of monthly bill |
| Software & subscriptions | 100% if business use |
4. Check your tax code
Login to your HMRC account and verify the code reflects your situation.
5. Calculate payments on account
If your tax bill is over £1,000, you'll owe payments on account on top — half of next year's projected bill on 31 January, half on 31 July.
6. File before the deadline
The 2026/27 deadlines are:
- 31 October 2026 — paper filing
- 31 January 2027 — online filing (and balance payment)
- 31 July 2027 — second payment on account
7. Set up a tax pot
The single biggest stress-reducer is paying tax-set-aside money into a separate account every month. LedgerlyPro estimates your liability live so you know exactly how much.
Next read: How VAT works for sole traders
