A complete guide to your Self Assessment tax return

Who has to file

You usually need a return if you are self-employed, a partner, a landlord, a company director with untaxed income, or you have foreign or capital gains HMRC cannot collect through PAYE. HMRC also issues notices to file. If you get a notice, you must file even if the tax is nil.

Registering late does not remove the duty. It just compresses the work into penalty season. If you should have been in Self Assessment earlier, that is often a disclosure of earlier years as well as this year’s form.

The pages that actually matter

Employment, self-employment, UK property, capital gains, foreign, and additional information are the common modules. You do not complete every page. You do complete every page that applies. Leaving off a property because ‘the letting agent dealt with it’ is a classic omission.

The tax calculation is only as good as the records. Bank statements, invoices, mileage logs and completion statements beat a reconstructed guess in March.

• Online deadline: 31 January after the tax year.
• Paper deadline is earlier — most people should file online.
• Balancing payment is due 31 January; payments on account are 31 January and 31 July.

Payments on account

If your last bill was over HMRC’s threshold and not all collected through PAYE, you usually pay 50 percent on account toward the following year, twice. That feels like paying twice. It is not — it is a prepayment. Reducing payments on account is possible if you expect profits to fall, but you need a reasonable basis.

Solaratax prepares and files the return, explains the three numbers on the statement, and diaries the July payment. Start at Self Assessment services or send your records.

Questions we are asked

What if I cannot pay on 31 January?

File on time anyway — late filing and late payment are different penalties. Then speak to HMRC about Time to Pay, ideally with a computation in hand.

Can I file without a UTR?

You need a Unique Taxpayer Reference to file. Register as soon as you know you need a return. Do not wait for January.

Does Making Tax Digital replace Self Assessment?

Making Tax Digital for Income Tax adds digital records and updates for qualifying sole traders and landlords. It does not mean you ignore the annual return. Confirm the latest timetable on GOV.UK.