Understand Self Assessment from start to finish.
Learn who may need to file a Self Assessment tax return, what information you may need, how the process works and what to consider before submitting your return.
A Self Assessment return brings your taxable income together.
Income, allowable expenses, tax reliefs and other information may need to be considered before filing.
What is Self Assessment?
Self Assessment is a system used by HM Revenue & Customs to collect Income Tax from people whose tax is not fully collected through PAYE.
You report your income and tax information to HMRC.
Depending on your circumstances, you may need to report income from self-employment, property, investments or other sources through a Self Assessment tax return.
The return is used to work out the Income Tax and, where relevant, National Insurance contributions that may be due.
Not everyone with income outside employment needs to file a return, so eligibility should be checked against the current HMRC rules.
Self Assessment becomes easier when you understand the purpose of each stage.
The process is not simply about submitting a form. You need accurate records, the right income information and an understanding of which expenses and reliefs may apply.
Identify your filing requirement
First establish whether your circumstances mean you need to complete a Self Assessment tax return.
Gather accurate information
Collect income records, expense information, tax documents and other details needed for the return.
Submit and review
Check the information carefully before submitting the return and make sure any tax due is paid by the relevant deadline.
Self Assessment can apply to different types of income.
The exact filing requirement depends on your circumstances. These are some common situations where Self Assessment may be relevant.
Self-employed individuals
Sole traders and other self-employed individuals may need to report business income and allowable expenses.
Landlords
Rental income can create tax-reporting obligations, depending on the individual's circumstances and current rules.
Investment income
Certain investment and savings income may need to be reported where the relevant reporting thresholds or rules apply.
High-income taxpayers
Some people with higher levels of income can have additional tax-reporting requirements.
Foreign or other income
Certain overseas income or other taxable income may need to be included depending on residence and tax rules.
Other taxable situations
Some less common circumstances can also create a Self Assessment filing requirement.
How the Self Assessment process works.
Think of your tax return as a sequence of practical steps rather than one large task.
Check whether you need to file
Review your circumstances and the current HMRC criteria to establish whether Self Assessment applies.
Register where required
If you need to file and are not already registered, follow the relevant HMRC registration process.
Gather your records
Bring together income, expenses, tax documents and other information needed to complete the return.
Complete and submit
Enter the required information, review the figures and submit the return through the appropriate HMRC process.
Pay what is due
Check the amount due and make payment by the relevant deadline, including any applicable payments on account.
Accurate records make tax returns much easier.
Good record keeping can help you report your income accurately, identify allowable expenses and support the figures included in your tax return.
Keep supporting records for the period required by HMRC and make sure they are complete enough to explain the figures reported.
Income records
Keep invoices, statements, payslips, rental records and other evidence of taxable income where relevant.
Business expenses
Record expenses that may qualify as allowable business expenses under the relevant rules.
Bank and payment records
Keep useful bank statements and payment records that support income and expense calculations.
Tax documents
Keep relevant tax certificates, pension information, dividend records and other supporting documents.
Previous returns
Previous tax returns and calculations can help you maintain consistency and identify changes.
Filing the return and paying the tax are separate steps.
After submitting a return, check the calculation and payment information carefully. Some taxpayers may also need to make payments on account.
Check the calculation
Review the tax calculation produced from the information included in your return.
Check the deadline
Make sure you understand the applicable filing and payment deadlines for your tax return.
Consider payments on account
Depending on your circumstances, HMRC may require advance payments towards a future tax bill.
Common Self Assessment mistakes to avoid.
A few simple checks can reduce the risk of errors and unnecessary stress when preparing your return.
Missing a source of income
Make sure all relevant taxable income is considered rather than relying on a single bank account or income statement.
Claiming unsupported expenses
Expenses should meet the applicable rules and be supported by appropriate records.
Filing or paying late
Late filing or payment can result in penalties or interest, so keep track of the relevant HMRC deadlines.
Submitting without checking
Review income, expenses, allowances and other figures before submitting the return.
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Self Assessment FAQs
Common questions about registration, tax returns, records, deadlines and payments.
Make Self Assessment easier to understand.
Understand the filing process, organise your records and explore the tax topics that can affect your return.