Top 5 questions on Self Assessment answered 

1 December 2023

HM Revenue and Customs (HMRC) has provided answers to the top 5 questions asked on the Self Assessment helpline. 

Do I need to fill in a tax return? 

Customers can use the online tool to check if they need to complete a tax return. They will need to answer a few simple questions and it will help them decide if they need to submit one. 

How do I fill in my online tax return?  

Customers can complete their tax return online using HMRC online services. For help filling in the return follow HMRC’s YouTube videos, and use the helpsheets, notes and forms.

How do I check how much tax I owe? 

HMRC works this out for customers based on their completed tax return. They can easily check and pay any tax owed via the HMRC app or via the online service. 

Where’s my Self-Assessment tax refund? 

Use the where’s my reply tool on GOV.UK to check response times based on how and when the claim was made. 

What happens if I can’t pay my tax bill? 

If customers cannot pay any tax owed in full, they can set up a payment plan, known as a Time to Pay arrangement. 

Interest will be payable on any outstanding payments after the deadline. 

HM Revenue and Customs (HMRC) is urging Self Assessment customers to use an ‘online first’ approach when seeking help to complete their tax return. 

There is a wealth of information and support available on GOV.UK to help customers complete their tax return for the 2022 to 2023 tax year ahead of the deadline on 31 January 2024.

Anyone completing a tax return for the first time can use HMRC’s step-by-step guide which explains what they need to do.