Do I Need to File a Self Assessment Tax Return? A Decision Guide

You may need to file a Self Assessment return if any of the following apply:

• You are self-employed with income above £1,000
• You owe the HICBC and it is not being collected through your PAYE tax code
• You have rental income above £2,500 per year (or any amount if you have expenses to deduct)
• You have dividend income above £10,000
• You have untaxed savings interest
• You need to claim higher-rate tax relief on pension contributions made via Relief at Source
• You have capital gains above the annual exempt amount
• You have foreign income that needs to be declared

You do not automatically need to file just because your income is above a certain amount. If all your income is taxed through PAYE and you do not have any of the situations above, you may not need to file.

If you are unsure whether you need to file, the HMRC online tool can help you check.

You earn £110,000 with a salary sacrifice pension. If salary sacrifice is your only complication and you have no other income, you may not need to file. But check whether you owe HICBC.

You earn £105,000 and contribute to a SIPP. If you paid into a SIPP or another relief at source pension, you may need to claim extra tax relief. You can often do this through Self Assessment, but in some cases you can claim directly from HMRC by asking them to adjust your tax code.

You earn £120,000 and received RSU vestings. If your employer reports everything through PAYE and you have no other income, you may not need to file. Check your P60 to see what has been reported.

You earn £65,000 and claim Child Benefit. You may need to file if you owe HICBC and HMRC has not adjusted your tax code to collect it.

Key dates for each tax year:

• 5 October: Register for Self Assessment if it is your first time
• 31 October: Paper return deadline
• 31 January: Online return deadline and payment due date

Late filing penalties start at £100 and increase. If you miss the 31 January deadline by 3 months, daily penalties of £10 can apply. After 6 months, a further 5% of tax owed may be charged.

If you are unsure whether you need to file, erring on the side of filing is generally safer than not filing.