Last verified: 12 October 2026 • Based on HMRC-published rates 2026/27
Do you need to do a Self Assessment tax return in the UK for 2026/27?
You must file a Self Assessment tax return with HMRC if your gross self-employment or side-hustle earnings exceeded £1,000 (trading allowance), you earned over £2,500 in untaxed property or savings income, you had dividend income over the £500 tax-free allowance, or you or your partner earned over £60,000 and claimed Child Benefit (High Income Child Benefit Charge). If your only income is PAYE employment under £100,000 with correct tax deducted, you do not need to file.
Self Assessment Filing Criteria (2026/27)
- Self-employed & Sole Traders: Gross business turnover above £1,000 trading allowance.
- Construction Industry (CIS): Subcontractors suffering 20% or 30% deductions claiming annual rebates.
- Property Landlords: Rental income above £2,500 net (or £10,000 gross).
- High Income Child Benefit Charge (HICBC): Adjusted net income exceeding £60,000 when receiving payments.
- Capital Gains Tax: Taxable gains exceeding the £3,000 annual exemption.
- Deadlines: Register by 5 October • Paper returns by 31 October • Online filing & tax payment by 31 January.
Statutory Self Assessment Deadlines for 2026/27
Missing an HMRC deadline incurs an immediate automatic £100 late filing penalty, even if you have no tax to pay. Here are the statutory milestone dates:
Who Does NOT Need to File a Tax Return?
Most UK workers do not need to file Self Assessment returns. HMRC automatically collects your statutory liability via PAYE payroll if:
- Your sole income is from an employer or occupational pension scheme where tax is deducted at source.
- Your side-hustle or trading turnover is less than £1,000 per year (fully covered by the Trading Allowance).
- Your savings interest falls within your Personal Savings Allowance (£1,000 basic rate, £500 higher rate).
- Your dividend income is below £500.
Related Calculators & Guides
Calculate your construction scheme deductions or check your child benefit clawback taper.
Frequently Asked Questions: Do I Need to Do a Tax Return?
Do I need to file a tax return if I am employed under PAYE?
No, standard PAYE employees whose only income is from their job do not need to file a tax return. Your employer deducts Income Tax and National Insurance automatically before paying you.
What is the trading allowance for side hustles?
The Trading Allowance gives you £1,000 of tax-free gross turnover each tax year. If your total gross income from casual services, selling online, or freelance work is under £1,000, you do not need to declare it to HMRC.
When is the deadline to register for Self Assessment?
You must register with HMRC by 5 October following the end of the tax year in which you earned the untaxed income. For the 2026/27 tax year (ending 5 April 2027), you must register by 5 October 2027.
What is the deadline for filing an online tax return?
The online filing deadline is midnight on 31 January following the end of the tax year. For 2026/27, the deadline is 31 January 2028. This is also the strict deadline for paying any balancing tax owed.
Do I need to file a tax return if I earn over £100,000?
Not automatically. HMRC removed the standalone requirement to file Self Assessment solely for earning over £100,000 in PAYE income, provided your tax code is correct and you have no untaxed income or HICBC liability.
Why do CIS subcontractors have to file a tax return?
Contractors deduct 20% or 30% flat from your labour invoices without applying your £12,570 Personal Allowance or business expenses. You must file a tax return to reconcile your bill and claim your annual tax rebate.
What happens if I file my tax return late?
HMRC issues an immediate £100 fixed penalty if you miss the 31 January deadline. After 3 months, penalties of £10 per day apply (up to £900), followed by 5% surcharges at 6 and 12 months, plus statutory interest on unpaid tax.
What are payments on account?
Payments on account are advance payments towards your next year’s tax bill. If your Self Assessment tax bill exceeds £1,000 (and less than 80% was deducted at source), HMRC requires two equal instalments: 31 January and 31 July.
Do I need to do a tax return for selling second-hand personal items?
Selling your own unwanted personal possessions (like old clothes or furniture on Vinted or eBay) is not taxable trading and does not require a tax return. Buying or making goods with the intention of reselling for profit is trading.
How do I tell HMRC I no longer need to do a tax return?
If you previously filed Self Assessment but no longer meet any criteria (e.g. stopped self-employment), you must contact HMRC or use their online portal to formally close your Self Assessment record. Never simply stop filing.