Self Assessment Tax Return: FAQs

Filing a Self Assessment tax return can seem like an intimidating task, and often HMRC’s guides are full of tax jargon that can be hard to sift through.  With the deadline coming up, there are several things you’ll need to know to be ready to submit yours on time. 

To help simplify things, GoSimpleTax has gathered the most frequently asked questions about filing self-assessment tax returns. Read on to find these, plus links to other helpful resources.

Do I need to file a Self Assessment tax return?

You will need to file a Self Assessment tax return if you are:

• self-employed as a ‘sole trader’ and earned more than £1,000
• a partner in a business partnership

If your income is only from wages or pension, you will not usually need to send a return. However, you may need to send one if you have any other untaxed income, such as:

• tips and commission
• money from renting out a property
• foreign income
• income from savings, investments and dividends

What are the deadlines for submitting a Self Assessment tax return?

• 31 October – Last day to file paper tax returns
• 31 January – Last day to file tax returns online

For more information regarding important tax return deadlines and payment dates.

What if I miss the tax return deadline?

You will get a fine of £100 if you miss the deadline for submitting your tax return or paying your bill.

If you miss the deadline by more than three months (1st May, onwards), you will get a £10 a day fine for every day that it’s late, up to £900 or 90 days.

How do I register for a Self Assessment tax return?

If you’ve never submitted a tax return before, you will first need to register at the HMRC website and get a UTR (Unique Taxpayer Reference) number. There are many ways you can do this–for more information read our guide on getting a UTR number.

What if I made a mistake on my tax return?

If you made a mistake on your tax return, you can still make amendments to it even after you’ve filed. For example, if you made a mistake for the 2018-2019 tax year, you have until 31 January 2021 to notify HMRC. 

Your bill will be updated and you may be owed tax or need to pay more.

Using GoSimpleTax can help you avoid making mistakes–the software uses the information you provide to help you through each section and notify you if it finds any possible errors.

How do I submit a Self Assessment tax return?

Preparing a Self Assessment tax return can be daunting. Lucky for you, GoSimpleTax has created a step-by-step guide to filing a tax return.

GoSimpleTax’s user-friendly tax software can help you automatically calculate your income, expenditure, and tax owed. It can help you minimise the burden of submitting tax returns by eliminating errors, saving you hours, and letting you access your record from anywhere you are. 

Take the stress and time out of filing your tax return this year, and focus on the things that matter. Start your free trial today to begin. 

Last updated 31st January 2020.

Other relevant articles on the site include

• 12 things every limited company director should know about reporting additional income via self assessment tax returns
• 7 most common self assessment tax return errors revealed
• How far back can HMRC investigate self assessment tax returns?
• Self assessment tax return checklist and tips
• Self assessment tax return deadline: how to file a tax return
• Self assessment tax return errors
• Self assessment tax return: a legal guide
• Self-employed? Don’t miss the self assessment tax return deadline
• Software or accountant for self assessment tax return support?
• Tax return: a step-by-step guide to completing your self assessment
• Top 6 self assessment tax return allowances: are you missing out?
• What can i claim in my self-assessment tax return?
• Why you should have your tax return reviewed by a tax professional
• Why could your self assessment tax return be investigated?

Blog content is for information purposes and over time may become outdated, although we do strive to keep it current. It's written to help you understand your Tax's and is not to be relied upon as professional accounting, tax and legal advice due to differences in everyone's circumstances. For additional help please contact our support team or HMRC.