Earning extra money from a side hustle can create tax responsibilities, even if it is not your main source of income.
For the 2025/26 tax year, some people who need to register for Self Assessment must tell HMRC by 5 October 2026. This is why anyone searching for HMRC side hustle register should check their position well before the deadline.
However, the 5 October deadline does not automatically apply to every person who earns money from a side hustle.
Whether you need to tell HMRC depends on the type and amount of income you receive and your individual circumstances. If you need to complete a tax return for the 2025/26 tax year and you have either never sent a tax return before or were previously registered but did not need to send one for the 2024/25 tax year, HMRC says you must tell them by 5 October 2026.
This guide explains who may need to register, how the £1,000 trading allowance works, and the other important deadlines for the 2025/26 tax year.
What Is the HMRC Side Hustle Registration Deadline for 2026?
For people who are newly required to complete a Self Assessment tax return for the 2025/26 tax year, the key date may be:
5 October 2026
HMRC says you must tell them by 5 October 2026 if you need to complete a tax return for the previous tax year and either:
- You have not sent a tax return before, or
- You were registered previously but did not need to send a return for the 2024/25 tax year
The 2025/26 tax year ran from 6 April 2025 to 5 April 2026.
If you meet these conditions, you can tell HMRC by registering for Self Assessment. In some cases, a person who was registered previously may need to reactivate their Self Assessment account instead.
If you tell HMRC after 5 October 2026, you could receive a penalty. HMRC may also give you a different filing deadline after registration, but its current guidance states that tax owed for 2025/26 must still be paid by 11:59 pm on 31 January 2027.
What Counts as a Side Hustle?
“Side hustle” is not a separate legal tax category. It is an informal term commonly used for activities that generate additional income alongside a main job or other source of income.
Examples can include:
- Freelance work
- Tutoring
- Photography
- Creating and selling products for profit
- Cake-making
- Social media work
- Providing paid services
- Online selling carried out as a trading activity
The important question is not whether you call the activity a side hustle. What matters is the nature of the income and whether you need to report it to HMRC.
For example, regularly buying goods with the intention of selling them for a profit may be treated differently from simply selling unwanted personal belongings.
Do You Need to Register With HMRC If Your Side Hustle Earns Less Than £1,000?
Not necessarily.
The UK has a £1,000 trading allowance for relevant trading and miscellaneous income.
If your total gross income or receipts from relevant trading activities for the tax year are £1,000 or less, you may be able to use the trading allowance. In many straightforward cases, this means you will not need to tell HMRC about that income or report it on a Self Assessment tax return.
However, there are exceptions and individual circumstances can differ.
For example, some people may choose to register even where their trading receipts are £1,000 or less because they need to do so for another reason, such as certain National Insurance, benefit or scheme-related purposes.
You should therefore check your position rather than assuming that earning under £1,000 always means you have no HMRC obligations.
Is the £1,000 Limit Based on Profit or Income?
The £1,000 trading allowance is based on relevant gross income or receipts, not profit.
This means you should not deduct your business expenses before deciding whether your total trading receipts exceed £1,000.
For example, if you earned £1,200 from eligible trading activities but spent £500 on related costs, your gross receipts would still be £1,200.
Where total relevant receipts are more than £1,000, you may need to report the income and work out your taxable profit under the rules that apply to your circumstances.
HMRC’s current side-hustle guidance also makes clear that the £1,000 threshold covers combined income from side hustles. For example, earning £600 from one trading activity and £500 from another would mean total side-hustle receipts of £1,100.
What If You Have More Than One Side Hustle?
The £1,000 trading allowance is not a separate £1,000 allowance for every side hustle.
Relevant income from qualifying trading activities must be considered together when checking how the allowance applies.
For example, if you earn:
- £700 from photography services
- £400 from freelance social media work
Your combined relevant trading receipts would be £1,100.
You should not assume that both activities can each use a separate £1,000 allowance.
The exact tax treatment can depend on the type of income and your circumstances.
How to Register With HMRC for a Side Hustle
If you have checked your circumstances and need to register for Self Assessment, you can tell HMRC by following its registration process.
How you register depends on your circumstances.
For example, a person starting as a sole trader may need to register for Self Assessment as self-employed. Someone who was previously registered but did not need to file a return for the previous tax year may need to reactivate their Self Assessment account.
Before registering, HMRC recommends checking whether you actually need to send a tax return.
Do not register simply because you have heard that everyone with a side hustle must complete Self Assessment. The correct action depends on your income and circumstances.
What Happens After You Register?
After registering, HMRC will provide the information you need to manage your Self Assessment obligations.
You should keep appropriate records to help you complete your tax return correctly.
Depending on your circumstances, this may include records of:
- Income received
- Business expenses
- Bank statements
- Sales records
- Invoices
- Receipts and other supporting documents
HMRC says that self-employed people should keep records that help them work out their business income and expenses.
Keeping records throughout the year can make it easier to prepare an accurate tax return later.
Other Important Self Assessment Dates for 2026/27
The 5 October 2026 date is not the only deadline to remember.
For the 2025/26 tax year, the main dates include:
5 October 2026
The deadline to tell HMRC you need to complete a tax return if you meet the conditions set by HMRC for the previous tax year.
31 October 2026
The normal deadline for HMRC to receive a paper Self Assessment tax return.
30 December 2026
The deadline for eligible taxpayers who want HMRC to collect tax owed through their PAYE tax code, provided they meet HMRC’s conditions.
31 January 2027
The normal deadline for submitting an online Self Assessment tax return.
It is also the normal deadline for paying tax owed for the 2025/26 tax year.
Some taxpayers may also have a first payment on account due on this date.
31 July 2027
The normal date for the second payment on account where payments on account apply.
Not everyone is required to make payments on account.
What Happens If You Miss the 5 October 2026 Deadline?
HMRC says you could get a penalty if you tell them after 5 October 2026 when you were required to notify them by that date.
If you register after 5 October 2026, HMRC’s current guidance says it will send you a letter or email with a different deadline for filing the tax return. This will be three months from the date on the letter or email.
However, for the 2025/26 tax year, HMRC says you must still pay the tax you owe by 11:59 pm on 31 January 2027, or you may face a penalty.
A later filing deadline should therefore not be confused with a later payment deadline.
Common Side Hustle Tax Mistakes to Avoid
Assuming Every Side Hustle Must Be Registered
Not every person earning extra money automatically needs to register for Self Assessment.
The £1,000 trading allowance and the nature of the activity can affect whether you need to tell HMRC about the income.
Looking Only at Profit Instead of Gross Receipts
The £1,000 trading allowance is based on relevant gross receipts, not the profit left after expenses.
Keep track of the total income from relevant activities before making assumptions about the allowance.
Treating Each Side Hustle as Having Its Own £1,000 Allowance
If you have more than one relevant trading activity, the allowance is not automatically £1,000 for each activity.
You need to consider the relevant rules and your combined income.
Assuming Online Platform Reporting Creates a New Tax
Online platforms may have reporting obligations in certain circumstances, but these rules do not create a new tax on side hustles.
Your underlying tax obligations depend on the nature and amount of your income and the tax rules that apply to you.
Waiting Until January to Check Your Position
If you are newly required to register for Self Assessment for the 2025/26 tax year, waiting until January may mean missing the 5 October notification deadline.
It is better to check your position as soon as possible.
Do You Need Help With Side Hustle Tax?
Tax rules depend on individual circumstances. Someone with a small amount of occasional income may have a different position from a person running a regular business alongside full-time employment.
Before deciding whether you need to register, check the type of income you received and your total relevant receipts for the tax year.
HMRC provides an online tool to help you check whether you need to file a Self Assessment tax return. If you are unsure how the rules apply to your situation, getting professional advice can also help you understand your reporting and tax obligations.
Frequently Asked Questions
- Do I have to register my side hustle with HMRC by 5 October 2026?
Not automatically. The deadline applies where you need to complete a Self Assessment tax return for the 2025/26 tax year and meet HMRC’s conditions for notifying them, including being a new Self Assessment filer or having previously been registered but not needing to file for 2024/25.
- What is the £1,000 side hustle allowance?
The £1,000 trading allowance can provide relief for qualifying trading and miscellaneous income.
In many straightforward cases, where total relevant receipts are £1,000 or less, the income may not need to be reported to HMRC. However, exceptions and individual circumstances can apply.
- Is the £1,000 allowance based on profit?
No. The allowance is based on relevant gross income or receipts, not profit after deducting expenses.
- What if I have two side hustles?
You should consider your relevant income from qualifying activities together. You should not assume you receive a separate £1,000 allowance for every side hustle.
- When is the online Self Assessment deadline for the 2025/26 tax year?
The normal deadline for filing an online tax return is 11:59 pm on 31 January 2027.
Final Thoughts
The hmrc side hustle register question does not have one answer for everyone.
For the 2025/26 tax year, 5 October 2026 is an important deadline for people who are newly required to notify HMRC that they need to complete a Self Assessment tax return, or who meet HMRC’s conditions after previously not needing to file.
Before registering, check whether your side hustle income needs to be reported. The £1,000 trading allowance, the nature of your activity, your total relevant receipts and your individual circumstances can all matter.
If you do need to complete a Self Assessment tax return, do not confuse the 5 October notification deadline with the normal online filing deadline of 31 January 2027.
Account Ease can help individuals and businesses understand their accounting and tax obligations and prepare for Self Assessment requirements based on their individual circumstances.
