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Guide
Do you have to file a Self Assessment tax return? Find out if HMRC is expecting a tax return from you this year.
File Self Assessment
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. Learn more about how FreeAgent can help.
Accountant or bookkeeper? Find out more
Key dates for your diary
- Tax year to file for:
- 6th April 2022 - 5th April 2023
- Online tax return deadline:
- Midnight, 31st January 2024
- Final payment of tax due:
- Midnight, 31st January 2024
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
Guide
Self 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.
Guide
How to register for Self Assessment Find out how and when to register for Self Assessment, and how the registration process might vary depending on your circumstances.
Guide
Working with your accountant during Self Assessment season Here’s how you can foster a winning relationship with your accountant during Self Assessment season.
Guide
Everything you need to fill out your Self Assessment tax return A list of all the things that you’ll need to have to hand in order to complete your tax return.
Guide
How 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.
Guide
How to calculate your business income for Self Assessment Find out what income you need to pay tax on - as well as the income you don’t!
Guide
Common tax return mistakes to avoid Follow these useful tips to avoid the most common mistakes that people make in the rush to file before the deadline.
Guide
How 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.
Guide
Payments on account: everything you need to know Payments 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.
The latest Self Assessment articles from our blog
Read more about Self Assessment on our blog.
20 November 2023
How is your Self Assessment tax bill calculated? We explain what information HMRC needs to calculate your tax bill, when you can see how much you owe and how FreeAgent can help.
15 November 2023
What happens if you can’t pay your Self Assessment tax bill? Even the most organised small business owners might occasionally struggle to pay their tax bill on time. Find out what to do if this happens to you.
9 November 2023
How to claim for allowable expenses and other types of tax relief on your Self Assessment tax return Find out the types of tax relief you might be able to claim for and how to go about it.
Downloadable guide
Get your Self Assessment checklist
Download your all-in-one guide to completing each step of your Self Assessment tax return.
Self Assessment videos
What information do I need to fill out my Self Assessment?
What taxable expenses can I include in Self Assessment?
How do I record pension contributions?
Complete your Self Assessment tax return with confidence
If you're a sole trader, limited company director or unincorporated landlord, 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.
