You must file a Self Assessment tax return if you're self-employed with gross income over £1,000, have rental income, are a company director, earned over £150,000 from any source, or received significant untaxed income. Around 12 million people file Self Assessment each year.
This guide helps you determine whether you need to file for the 2024/25 tax year (deadline: 31 January 2026).
Quick Check: Do I Need to File?
Answer these questions for the 2024/25 tax year (6 April 2024 – 5 April 2025):
Definite Yes — You Must File
| Situation | Threshold | |-----------|-----------| | Self-employed (sole trader) | Gross income over £1,000 | | Partner in a business partnership | Any partnership income | | Company director | Any (except non-profit with no pay/benefits) | | Total income from all sources | Over £150,000 | | Rental income | Over £2,500 (or any amount if claiming expenses) | | Untaxed foreign income | Any taxable amount | | Capital gains | Over £3,000 annual exempt amount | | Savings/investment income | Over £10,000 | | HMRC sent you a notice to file | Required regardless of income |
Maybe — Check Your Specific Situation
| Situation | When You Must File | |-----------|-------------------| | Child Benefit recipient | Income over £60,000 (High Income Child Benefit Charge) | | Employee with expenses | Claiming over £2,500 in employment expenses | | Pension contributions | Exceeding annual allowance (£60,000) | | Untaxed tips or commission | Significant amounts not reported through PAYE | | Received P800 from HMRC | States you owe tax that can't be collected through PAYE |
If you're unsure, use HMRC's online tool to check.
Self-Employed Individuals
Who Counts as Self-Employed?
You're self-employed if you work for yourself rather than an employer. This includes:
- Freelancers — designers, writers, developers, consultants
- Tradespeople — plumbers, electricians, builders, decorators
- Gig economy workers — Uber drivers, Deliveroo riders, Amazon Flex
- Online sellers — eBay, Etsy, Amazon, Vinted (if regular trading)
- Tutors and coaches — private lessons, personal training
- Photographers and creatives — selling services directly to clients
The £1,000 Trading Allowance
If your gross self-employment income is £1,000 or less, you don't need to register for Self Assessment. The Trading Allowance provides tax-free income for casual or small-scale trading.
Above £1,000: You must register and file Self Assessment.
You can either:
- Use the £1,000 Trading Allowance (no expenses claimed)
- Claim actual expenses (usually better if expenses exceed £1,000)
When to Register
Register for Self Assessment by 5 October following the tax year you started self-employment.
Example: You started freelancing in July 2024. Register by 5 October 2025 to file your 2024/25 return by 31 January 2026.
Register at gov.uk/register-for-self-assessment.
Learn more: Sole Trader Tax Guide
Landlords and Property Income
Rental Income Over £2,500
If you receive more than £2,500 in rental income during the tax year, you must file Self Assessment.
This applies to:
- Buy-to-let property landlords
- Airbnb and short-term rental hosts
- Holiday let owners
- Those renting out a second home
Any Rental Income (If Claiming Expenses)
Even with rental income under £2,500, you must file if you want to claim property expenses against the income. Allowable expenses include:
- Letting agent fees
- Repairs and maintenance
- Insurance
- Ground rent and service charges
- Accountant fees
Property Allowance
Similar to the Trading Allowance, a £1,000 Property Allowance covers small amounts of rental income.
Under £1,000: No need to file (unless other criteria apply) £1,000 – £2,500: File only if claiming expenses Over £2,500: Must file
Rent a Room Scheme
If you rent a room in your main home, the Rent a Room Scheme allows up to £7,500 tax-free.
- Under £7,500: No need to file for this income
- Over £7,500: Must file and pay tax on the excess
Learn more: Landlord Tax Guide
Company Directors
Most Directors Must File
If you're a director of a limited company, you typically need to file Self Assessment to report:
- Salary from the company (even if taxed through PAYE)
- Dividends received from company profits
- Benefits in kind (company car, private medical insurance)
Exceptions
You don't need to file if you're a director of:
- A non-profit organisation, AND
- You receive no pay or benefits from the role
Example: You're an unpaid charity trustee who is technically a director. No Self Assessment needed for this role.
Dividend Reporting
Directors often take low salary plus dividends for tax efficiency. Report dividends on your Self Assessment:
| Dividend Amount | Tax Treatment | |-----------------|---------------| | First £500 | Tax-free (Dividend Allowance 2024/25) | | £501 – £37,700 | 8.75% (basic rate) | | £37,701 – £125,140 | 33.75% (higher rate) | | Over £125,140 | 39.35% (additional rate) |
Dividend tax bands assume no other income uses the basic/higher rate bands.
High Earners (Over £150,000)
£150,000 Threshold
If your total income from all sources exceeds £150,000, you must file Self Assessment—even if all your income is taxed through PAYE.
Total income includes:
- Employment salary and bonuses
- Self-employment profits
- Rental income
- Dividends and interest
- Pension income
- Any other taxable income
Why High Earners Must File
At this income level:
- You may owe additional tax not collected through PAYE
- The Personal Allowance starts reducing (gone entirely at £125,140)
- Complex reliefs and charges may apply
- HMRC requires the complete picture of your finances
Child Benefit Claimants
High Income Child Benefit Charge
If you or your partner receive Child Benefit and either of you earns over £60,000, the higher earner must file Self Assessment.
The High Income Child Benefit Charge claws back Child Benefit:
| Adjusted Net Income | Child Benefit Clawed Back | |---------------------|---------------------------| | £60,000 or under | None | | £60,001 – £80,000 | Proportionate amount | | Over £80,000 | 100% (all Child Benefit) |
Example: You earn £70,000 and receive £2,000 Child Benefit. You must file Self Assessment and pay back approximately £1,000 (50% of the benefit).
Opting Out
You can opt out of receiving Child Benefit to avoid filing. However, the person who stays home with children should still claim (but not receive payment) to protect their National Insurance record.
Capital Gains
When to Report Capital Gains
You must file Self Assessment if your capital gains exceed the Annual Exempt Amount (£3,000 for 2024/25).
Capital gains arise from selling:
- Property (other than your main home)
- Shares and investments
- Cryptocurrency
- Valuable items worth over £6,000
Property Sales
If you sell a property that isn't your main residence:
- Report and pay CGT within 60 days of completion
- Also report on your Self Assessment return
- CGT rates: 18% (basic rate) or 24% (higher rate) for residential property
Annual Exempt Amount
The first £3,000 of capital gains each year is tax-free. Above this, you must file Self Assessment.
Note: Even gains under £3,000 may need reporting if total proceeds exceed £50,000.
Employees: When PAYE Isn't Enough
Most employees don't need to file Self Assessment—tax is collected automatically through Pay As You Earn (PAYE). But you must file if:
Untaxed Income
- Savings interest above your Personal Savings Allowance (£1,000 basic rate, £500 higher rate)
- Dividends above the Dividend Allowance (£500 for 2024/25)
- Foreign income not taxed at source
Employment Expenses
If you have work-related expenses over £2,500 that your employer doesn't reimburse, file Self Assessment to claim:
- Professional subscriptions
- Work equipment
- Home working (if not covered by employer)
- Uniform cleaning
Underpaid Tax (P800)
If HMRC sends you a P800 showing you underpaid tax and it can't be collected through your tax code adjustment, you may need to file Self Assessment.
Foreign Income and Offshore Matters
UK Tax Residents
If you're a UK tax resident, you must declare worldwide income. File Self Assessment if you receive:
- Foreign employment income
- Overseas rental property income
- Foreign dividends and interest
- Foreign pension income
- Gains from selling overseas assets
Non-Domiciled Individuals
Non-doms may use the remittance basis, but must still file Self Assessment to make this claim.
Notice to File
HMRC Can Require Filing
Even if none of the above criteria apply, you must file if HMRC sends you a notice to file (SA316 form).
HMRC may issue a notice if:
- Their records show you may have untaxed income
- You filed previously and they expect a return
- Information from third parties suggests you should file
Withdrawing from Self Assessment
If you no longer need to file (e.g., you've stopped self-employment), tell HMRC. Otherwise, they'll continue expecting returns and may charge penalties for "late" filing.
Request to withdraw from Self Assessment
Consequences of Not Filing
Penalties
If you should file but don't:
| Delay | Penalty | |-------|---------| | 1 day late | £100 (even if no tax owed) | | 3 months late | £10/day up to 90 days (max £900) | | 6 months late | Greater of £300 or 5% of tax due | | 12 months late | Additional £300 or 5% of tax due |
Maximum penalty: £1,600 plus up to 100% of tax owed for serious cases.
Interest on Unpaid Tax
Interest accrues on unpaid tax from the due date. The current HMRC interest rate is published on GOV.UK.
Investigation Risk
Not filing when required increases the chance of HMRC opening an enquiry. They receive data from:
- Banks (interest payments)
- Employers (P60/P45 data)
- Companies House (director appointments)
- Land Registry (property transactions)
- Overseas tax authorities
How to Register for Self Assessment
If you need to file, register by 5 October following the tax year:
- Go to gov.uk/register-for-self-assessment
- Create a Government Gateway account (if you don't have one)
- Select your registration type:
- Self-employed/sole trader
- Not self-employed (e.g., landlord, company director)
- Partnership
- Complete the registration
- HMRC posts your Unique Taxpayer Reference (UTR) within 10 working days
Your UTR is a 10-digit number required to file your return.
Making Tax Digital Changes
From April 2026, Self Assessment changes under Making Tax Digital for self-employed and landlords:
| Income Threshold | MTD Start Date | |------------------|----------------| | Over £50,000 | 6 April 2026 | | Over £30,000 | 6 April 2027 |
MTD requires quarterly digital submissions plus a final declaration, using HMRC-recognised software.
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