There’s a lot to remember if you need to submit a Self Assessment tax return to HMRC.
To help you keep track, our Self Assessment checklist details everything you need to include on your tax return.
Does my Self Assessment need to show money I’ve already paid tax on?
Yes, your Self Assessment tax return should refer to everything you’ve earned during the period you’re reporting on – even if you’ve paid tax on it already! This doesn’t mean you’ll pay tax on that money again, but you’ll need to include it on your return so HMRC can use this information to calculate your tax bill correctly.
For example
You work for an employer who pays you a salary of £45,000. You also have a side hustle which makes a profit of £15,000 in the same tax year.
Each individual amount is in the 20% tax band, but your final tax bill is based on the total amount you earn in a year.
You’ve already paid tax on your wages through your employer, so adding your self-employed profits to your existing earnings puts some of your profits into the higher rate tax bracket so you’ll be taxed at 40% on that chunk.
Reporting this on your tax return is much better than getting a scary letter from HMRC because they’ve linked your employer’s records to your self-employed income!
Employment details for Self Assessment
Your Self Assessment tax return will ask for the details of any employments or directorships you held during the tax year. This might include work you’ve done for an employer, or as an employee or director of your own company.
You’ll need to provide the details of your earnings and tax for each employment or directorship separately in its own section of your tax return. If you post a paper Self Assessment tax return, you’ll need to include a separate supplementary SA102 form for each one.
- Earnings and tax information will be shown on your P60 for that tax year (or your P45 if you left)
- If you worked for more than one employer in a tax year, make sure you include all of them on your return! You’ll need to supply the PAYE reference number (also known as an Employer Reference Number) for each one too.
- You’ll also need to tell HMRC about any Benefits in Kind you receive. Your employer should provide the details of any benefits they report.
Income from a pension
Your Self Assessment tax return should also include the details of any pension income or taxable lump sums you receive in a tax year.
- If it’s an occupational pension (one set up by your employer) then your P60 or certificate of pension paid will show how much pension you’ve received
- Your notification letter will tell you information about your state pension
- The provider will send you a pension statement if you have a private pension
It’s also useful to declare payments you make towards your pension pot, to make sure you don’t miss out on any tax relief!
Your self-employment and partnerships
Whether you made a profit or a loss you’ll need to include your self-employment activities on your tax return. You should complete a separate section for each self-employment (or a separate SA103 Form if you submit a paper return).
- Refer to your bookkeeping records for the income and expenses figures you’ll need to report
Investment and other income
If you receive any income from investments or other sources, then declare this on your Self Assessment return too. There are several potential sources, so we’ve set out a table which shows the kind of investment income you might have, and which documents show the information you need.
| Investment income type | Documents to refer to |
| Dividends from a UK company or unit trust, including shares (or units in lieu of dividends) | Dividend/distribution vouchers showing the dividend received, as well as the date and tax credit. |
| Income from trusts, settlements, Deeds of Covenant and estates | R185 or certificates of income and tax deducted. |
| Income from property | All income and expenditure records, including any mortgage interest statements. |
| Interest from banks and building societies | Certificates of interest received and tax deducted. |
| Interest from banks or building societies, received gross | Statements of interest received. |
| Money withdrawn from life assurance policies or bonds | Your Chargeable Event Certificate from the life assurance company. |
| National Savings interest received gross | Statements of interest received. |
| Overseas income | This might be in the form of dividend vouchers or other documents. |
Your other relevant outgoings
There might be costs associated with your self-employed business which should also be included on your Self Assessment tax return (so you can claim all the tax relief you’re entitled to!).
| Types of outgoings | Documents or examples |
| Employment expenses |
|
| Gift Aid or Deed of Covenant payments |
|
| Qualifying loans and mortgages |
|
| Student Loan repayments | |
| Other payments qualifying for tax relief |
|
Capital Transactions
If you make a profit (or ‘gain’) from disposing of an asset then you might need to report this on your Self Assessment tax return in order to pay Capital Gains Tax. Disposing of an asset usually means you’ve sold it, but it can also mean you’ve given it away, swapped it, or been compensated in another way for its loss.
Tax returns can be stressful! Learn more about our online accounting services, including support with your Self Assessment tax return. Call 020 3355 4047 and get an instant online quote.
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