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The Complete Self Assessment Tax Return Checklist

The Complete Self Assessment Tax Return Checklist

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 when sending your tax return.

Do I need to submit a Self Assessment tax return?

If you earned more than the £1,000 trading allowance from self-employed sole trader or freelance work in the last tax year, or more than £1,000 of property income, then you’ll usually need to submit a Self Assessment tax return.

Do I Need to Pay Tax on My Side Hustle Hobby BusinessDo I Need to Pay Tax on My Side Hustle Hobby Business 1

You’ll also need to send a return if you’re a partner in a business partnership, or if you earn money which isn’t from your employer or pension. For instance, if you receive dividend payments, and need to report them so you can pay Dividend Tax.

Where do I find my 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 that you’ve done for an employer, or as an employee or director of your own company.

You’ll need to provide the details of how much you earned from each employment, and any tax that you’ve already paid on it. For instance, the tax that your employer deducts when they pay your wages. If you submit your Self Assessment tax return using the paper version of the form, 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 employee Benefits in Kind that 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 that 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!

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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).

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 that you can also include on your Self Assessment tax return.

Types of outgoings Documents or examples
Employment expenses
  • A list of tax deductible expenses such as professional subscriptions or travel expenses
  • Pension contributions paid by you
  • Payments made (dates, amounts, policy details) and copy documentation
Gift Aid or Deed of Covenant payments
Qualifying loans and mortgages
  • Lender’s statements showing interest paid and tax relief given
Student Loan repayments
  • Student Loans Company statement
Other payments qualifying for tax relief
  • For instance, payments to other people.

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 this means that you’ve sold it, but it can also mean that 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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