Skip to main content 
Guide
Do you have to file a Self Assessment tax return? Find out if HMRC is expecting a tax return from you this year.
Self Assessment –
ace it with confidence
Find out everything you need to know to feel confident about Self Assessment, including key deadlines, who needs to file and how to complete your tax return.
How FreeAgent can help
Key dates for your diary
- Tax year to file for:
- 6th April 2021 - 5th April 2022
- Online tax return deadline:
- Midnight, 31st January 2023
- Final payment of tax due:
- Midnight, 31st January 2023
Breeze through Self Assessment with our helpful guides
Not sure where to start with your tax return? Browse through our topics and guides below to find the information you’re looking for.
Before the Self Assessment deadline
- GuideSelf Assessment deadlines: key dates you need to know
Our guide to the key Self Assessment dates throughout the year should help you avoid any nasty surprises.
GuideHow to register for Self AssessmentFind out how and when to register for Self Assessment, and how the registration process might vary depending on your circumstances.
-
GuideLearn the lingo: key Self Assessment terms explainedA breakdown of some of the key terms you’ll come across as you complete your Self Assessment tax return.
GuideWorking with your accountant during Self Assessment seasonHere’s how you can foster a winning relationship with your accountant during Self Assessment season.
GuideEverything you need to fill out your Self Assessment tax returnA list of all the things that you’ll need to have to hand in order to complete your tax return.
- GuideHow to complete your Self Assessment tax return
Find out which sections of the tax return you’ll need to complete and what information you’ll need to provide.
GuideHow to calculate your business income for Self AssessmentFind out what income you need to pay tax on - as well as the income you don’t!
GuideCommon tax return mistakes to avoidFollow these useful tips to avoid the most common mistakes that people make in the rush to file before the deadline.
- GuideHow to pay your Self Assessment tax bill
Learn more about the different ways you can pay your tax bill and how long it will take for your payment to reach HMRC.
GuidePayments on account: everything you need to knowPayments on account often catch business owners out. Here’s everything you need to know.
After the deadline
Guide
Missed the Self Assessment deadline? Here’s why you shouldn’t panic It’s going to be OK! If 31st January has been and gone, follow the tips in this guide to help minimise the impact of missing the deadline.
Guide
How to amend your tax return after you've filed it Made a mistake on your tax return? Here’s how to fix it.
Guide
Do you have a 'reasonable excuse’ for missing the Self Assessment deadline? Find out what HMRC might accept as a ‘reasonable excuse’ for missing the Self Assessment deadline.
The latest Self Assessment articles from our blog
Read more about Self Assessment on our blog.
3 November 2022
Self Assessment: accounting for Universal Credit, pension contributions and student loans on your tax return Here’s how to account for Universal Credit, pension contributions and student loan repayments on your Self Assessment tax return.
1 November 2022
How to tell HMRC about a change to your personal details In this article, we explain why it’s important for HMRC to have your up-to-date details and the steps you need to take to inform them of any changes.
20 October 2022
How to claim for allowable expenses and other types of tax relief on your Self Assessment tax return Find out how to claim for allowable expenses and other types of tax relief when completing your Self Assessment tax return.
Upcoming Self Assessment events
We’re hosting a wide range of events in the run up to the January deadline to help you get to grips with Self Assessment. Catch up on previous events you missed.
Live Facebook Q&A: Get confident about Self Assessment
Join our Chief Accountant live on Facebook to ask any burning questions about Self Assessment.
Find out more Live Facebook Q&A: Get confident about Self Assessment
Join our Chief Accountant live on Facebook to ask any burning questions about Self Assessment.
Find out more 
Downloadable guide
Get your Self Assessment checklist
Download your all-in-one guide to completing each step of your Self Assessment tax return.
Complete your Self Assessment tax return with confidence
If you're a sole trader or a limited company director, FreeAgent works away in the background to calculate your Self Assessment liability and prepare your tax return.
Get Self Assessment tax-confident Already a FreeAgent customer?
Our Knowledge Base has lots of helpful information about filing your Self Assessment tax return using FreeAgent.
