Being Self-Employed can be a fascinating experience, especially when you are starting as a freelancer, running a small business, or a sole proprietor. However, along with finding clients and earning, you also have several tax duties to complete.
The first thing to do is to find out if you are required to register for self-assessment with HMRC. If you started working as self-employed in tax year 2025-26, then you are usually expected to inform HMRC of that by 5th October 2026 if you are required to file a tax return.
Missing the register self-employed deadline can lead to tax problems that could have been easily avoided.
When Is The Self-Employed Registration Deadline?
The self-employed registration deadline for the self-assessment registration is 5 October following the end of the tax year when the person becomes self-employed.
The UK tax year extends from 6 April to 5 April each year. If you started trading between 6 April 2025 and 5 April 2026, then your self-employed registration deadline might be 5 October 2026.
For Instance:
| Your Trading Commencement | Registration Deadline | Tax Return and Payment Deadline |
| 13 May 2025 | 5 October 2026 | 31st January 2027 |
| 20 September 2025 | 5 October 2026 | 31st January 2027 |
| 2 March 2026 | 5 October 2026 | 31st January 2027 |
Registration and online tax return submission deadlines are two different issues. Being registered until 5 October 2026 doesn’t necessarily mean that you have to submit your tax return by that time.
Do You Really Need To Register As Self-Employed?
All those earning money on their own don’t necessarily have to register themselves as self-assessment taxpayers.
As per HMRC rules, you will be required to fill in a tax return form if you were self-employed as a sole trader and earned above £1,000 before allowance of expenses in that particular tax year. There are other reasons as well because of which you may need to register yourself.
If you are confused as to whether you need to register or not, there is a checker available on the HMRC website before you register.
How To Register For Self-Assessment?
In case you figure out that you need to register for Self-Assessment, you can register through the official website of the UK government.
You are required to provide relevant personal and business information to complete the registration process happen via an online platform. After successful registration, HMRC will provide you with a unique tax number that you will require when doing your Self-Assessment.
In case you have been registered before for self-assessment but didn’t file your tax return in the previous tax year, you might be required to activate your already existing Self-Assessment account.
What Happens Once You Are Registered?
Registration is just the start. After registration, you must ensure that you have kept proper financial records and are ready for your tax return.
According to HMRC, some financial records that you should keep include:
- Your sales and other business income
- Your bank statements
- Your receipts and invoices
- Your business expenses
- Any other financial records
This will make it easier for you to calculate your taxable profit. It’s always wise to save money throughout the year and not when your tax bill arrives.
When Should You Complete Your First Tax Return?
For the tax year of 2025-26, the due date for filing the online self-assessment tax return is 31 January 2027, and tax payments are due on or before the same date.
Your online return can be completed starting from 6 April 2026, so you don’t have to wait for January.
An early submission allows better financial planning since you will know how much tax you owe. In some cases, there will be a 31st July due date for payments on account.
What Happens If You Miss The Self-Employed Registration Deadline?
If you have been asked to register yourself and miss the 5 October deadline, don’t just forget about it.
According to HMRC, there is a possibility of a fine if you register after 5 October. There could be a penalty imposed on you if you register later and pay nothing or an amount less than the total tax bill by the specific date.
It is better if you find out that you have missed the deadline, then register right away and find out what steps to take.
Don’t Mistake Registration For Filing
Perhaps one of the most common misconceptions about becoming self-employed is that the 5 October deadline will mean your tax return is due on that day as well. But it’s not like that.
These are the processes you should follow:
- Figure out whether you have an obligation
Ensure that there is an obligation on your part to file self-assessment tax returns.
- Register before 5 October
If you need to file a tax return for last year, then make HMRC aware of it.
- File and pay before 31st January
As far as the tax year 2025-26 is concerned, the deadline for filing and paying online will be 31st January 2027.
This might assist you when you become self-employed for the first time.
Mistakes that Newly Self-Employed People Commit
Running a business usually implies focusing on clients, pricing, and delivery of your work. The administration of taxes might easily drop down the list of priorities.
Among the typical mistakes committed by self-employed people are:
- Not thinking about the taxes till January
- Not collecting invoices and receipts
- Making private and business transactions together without any record
- Not thinking about the allowable business expenses
- Not answering HMRC letters
- Basic accounting practice will help you avoid most of these mistakes
How Can An Accountant Assist?
An accountant can assist you with managing your tax obligations as a self-employed person. The accountant will inform you how to organize your accounts and submit the self-assessment form.
The accountant’s services may be useful in case you have several sources of income or substantial expenses related to your business activities.
Need Assistance In Maintaining Your Self-Employed Accounts?
Becoming a self-employed person is simple if your accounting duties are sorted out. We, Lexarox Accounts, can help self-employed people and small businesses from the UK maintain their accounting and tax requirements so that you can be well-prepared for all the deadlines.
From maintaining all your financial details to getting your self-assessment tasks done, we can help you save lots of effort in this regard.
If you have become self-employed recently and are not sure of your tax duties, then contact our professionals at Lexarox Accounts for help with accounting.
Conclusion
Registering as self-employed before the self-employed registration deadline is essential for people who have started their venture in the past few months. If you registered yourself as self-employed during the 2025-26 tax year and have to fill out a self-assessment tax form, then you should inform HMRC about your status by 5 October 2026. Then, the completion of your tax return and making the payment will be due by 31st January 2027.
Never wait until the last moment to register for tax returns. You must take all steps from the very beginning.
Frequently Asked Questions
What is the self-employed registration deadline?
If you need to register for the 2025/26 tax year, then this is the deadline to do so – 5 October 2026.
When is my first self-assessment return due?
In respect of the 2025/26 tax year, the deadline for making an online tax return would be 31st January 2027.
Does everybody who is self-employed need to register?
No, they don’t. HMRC says that generally sole traders will have to make a tax return if their self-employed income exceeds £1,000 net of allowable expenses, although there are other situations where it might be required as well.
What if I register after 5 October?
You should get it done as soon as possible, according to HMRC. They say that you might receive a penalty for being late.
Do I need to register if I was previously self-employed?
Maybe not. If you have been previously registered but didn’t need to file a return in the previous year, then you might need to activate your current Self-Assessment account instead.
Can I register myself as self-employed online?
Yes. You can register for self-assessment online using the official website of the UK government.
What records must the self-employed keep?
One should maintain the appropriate financial records, like receipts and bank statements, that will help you fill in the tax return form.
Is it possible to file the tax return before the deadline?
Yes. For the 2025-26 tax year, online submission will be available between 6 April 2026 and 31st January 2027.
