Self Assessment, sorted: filed right and on time
We prepare, check and file your Self Assessment tax return, make sure you claim everything you're entitled to, and tell you exactly what to pay and when. No jargon, and no last-minute panic before the 31 January deadline.
Reviewed July 2026. Figures are correct at the date of review. Always check GOV.UK for the latest.
What it is
Self Assessment is how HMRC collects tax on income that isn't taxed automatically at source. You report your income and gains for the tax year, and pay any tax due. Get it right and it's straightforward; get it wrong or leave it late and it's stressful and expensive.
Who needs it
Typically the self-employed and sole traders, landlords, company directors with untaxed income, higher earners, and anyone with other income HMRC hasn't already taxed. If you're unsure whether you need to file, we'll confirm it for you.
Key dates
- Register for Self Assessment by 5 October after the end of the tax year
- Paper returns are due by 31 October
- Online returns, and any tax you owe, are due by 31 January
- Where they apply, payments on account fall due on 31 January and 31 July
From April 2026, Making Tax Digital for Income Tax means sole traders and landlords with qualifying income over £50,000 must keep digital records and report quarterly. We'll get you ready ahead of time.
Common mistakes
- Registering or filing late and taking avoidable penalties
- Under-claiming allowable expenses and reliefs
- Forgetting payments on account and getting caught short in January
- Leaving digital records until MTD forces the change
How Xpert helps
We prepare and file your return, claim everything you're due, and tell you exactly what to pay and when, well before the deadline. You get a dedicated accountant, a fixed fee with no surprises, and plain-English answers within three hours.
Sole trader or landlord? Take our 2-minute quiz for a tailored recommendation.
Frequently asked questions
Common questions about Self Assessment.
Do I need to file a Self Assessment?+
You usually need to file if you're self-employed, a landlord, a company director with untaxed income, a higher earner, or you have other income HMRC hasn't already taxed. If you're not sure, we'll check for you.
When is the deadline?+
Register by 5 October after the end of the tax year. Paper returns are due by 31 October, and online returns, plus any tax you owe, by 31 January. We prepare yours well ahead so you never cut it fine.
What are payments on account?+
They're advance payments towards your next tax bill, usually made in two instalments: by 31 January and 31 July. We work out whether they apply to you and what to set aside, so there are no nasty surprises.
What is Making Tax Digital for Income Tax?+
From April 2026, sole traders and landlords with qualifying income over £50,000 must keep digital records and send quarterly updates to HMRC. We get your records ready now, so the switch is painless.
What can I claim to reduce my tax?+
There are allowable expenses and reliefs most people miss. We make sure you claim everything you're genuinely entitled to, without overstepping the rules.
Can you help if I'm already late?+
Yes. We'll bring your returns up to date, deal with HMRC, and help minimise penalties and interest, then keep you on time from now on.
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