Registering for Self Assessment: HMRC answers your questions
The 5 October deadline to tell HMRC if you need to complete a self assessment tax return is approaching. To avoid any misunderstandings you may have about what needs to be reported, HMRC has provided us with answers to common questions to help you get your tax right.
What is Self Assessment and who needs to register?
Anyone receiving untaxed income – either in cash or into a bank account – may need to report it to HMRC and pay Income Tax through Self Assessment. Check how to register for Self Assessment – GOV.UK
What is the registration deadline?
You must tell HMRC by 5 October 2026 if you need to complete a tax return for the 2025–2026 tax year.
Do I need to register every year?
No. If you completed a Self Assessment return last year, you do not need to register again.
What if I’ve just become self-employed?
You must tell HMRC about your new business or work, even if you’ve done Self Assessment before.
Do I need Self Assessment if I already pay tax through PAYE?
Yes. You may still need to complete a return if you have additional types of income or circumstances.
What are common reasons you may need to complete a tax return?
You may need to complete a return if you:
• Are newly self-employed or a sole trader earning over £1,000
• Are a partner in a business partnership
• Receive untaxed income over £2,500
• Earn online trading income over £1,000
• Have cryptoasset gains or income
• Claim Child Benefit with income over £60,000
• Earn interest, dividends, or rental income above thresholds
• Need to pay Capital Gains Tax
• Claim job expenses over £2,500
Is there help to check if I need to complete a tax return?
You can use HMRC’s online tool:
Check if you need a tax return
What happens after I register?
HMRC will issue you a notice to file, and you can submit your return anytime before the deadline.
What is the deadline for submitting the tax return?
The deadline is 31 January 2027.
What if I stop being self-employed?
You must tell HMRC as soon as possible, or before 31 January 2027, to avoid penalties.
Construction Industry Scheme
Do I need to register for Self Assessment if I work in construction?
Yes. If you work as a self-employed individual, subcontractor, or sole trader in the construction industry, you are usually required to register for Self Assessment and submit a tax return every year. This applies even if you are paid under the Construction Industry Scheme (CIS).
What is the Construction Industry Scheme (CIS)?
The Construction Industry Scheme is a set of rules set out by HMRC for contractors and subcontractors in the construction sector. Under CIS, contractors deduct money from a subcontractor’s payments and pass it to HMRC as advance payments towards the subcontractor’s tax and National Insurance.
I’m paid under CIS – do I still need to file a tax return?
Yes. Even though tax is deducted from your payments under CIS, you must still complete a Self Assessment tax return. This allows you to declare your income and claim back any allowable expenses, and you may be due a refund if too much tax has been deducted.
I am a contractor in construction – what are my responsibilities?
If you pay subcontractors for construction work, you must register as a contractor with HMRC. You are responsible for deducting the correct amount of tax under CIS from your subcontractors’ payments and submitting monthly returns to HMRC. You may also need to complete a Self Assessment tax return for your own income.
What expenses can I claim as a construction worker?
As a self-employed person or subcontractor, you may be able to claim expenses for items such as tools, protective clothing, travel between sites, and other business-related costs. These claims are made when you complete your Self Assessment tax return.
How do I register for the Construction Industry Scheme?
You can register for CIS online on GOV.UK. If you are a subcontractor, you should register before you start working. Contractors must register before they pay any subcontractors. Registration for CIS is separate from registering for Self Assessment, so you may need to complete both processes
High Income Child Benefit Charge
What is the HICBC PAYE digital service?
HICBC is paid by customers who get Child Benefit (CHB) with an individual income or partner’s income of between £60-£80k a year. A new service allows eligible customers to pay the High Income Child Benefit Charge through their PAYE tax code – known as being ‘coded out’. This removes the need to register for Self Assessment and submit a tax return solely for HICBC purposes. The charge will be taken monthly via your salary as your tax code will be amended. More information on eligibility and how to switch is available on gov.uk.
Who is eligible to use the service?
The service is available to customers who:
- Are paying the charge for the first time in the 26/27 tax year because they’re new parents
- Are over the threshold and begun a partnership with someone who is claiming Child Benefit
- Have recently had a pay rise that now means they’re over the threshold and liable to pay the HICBC
- Are existing customers who only complete SA for HICBC purposes. They will have to call HMRC once to be deregistered from SA and begin paying their HICBC via their tax code.
I already pay HICBC through Self Assessment. Can I switch?
Yes, if HICBC is your only reason for completing Self Assessment. You will need to call HMRC once to be deregistered from Self Assessment. After that, you can pay through your tax code.
What is HMRC changing about Self Assessment forms? Where is HMRC getting this data?
HMRC prepopulates the High Income Child Benefit Charge section of the Self Assessment tax return with Child Benefit data that HMRC already holds. This means customers will see relevant information already filled in when they access this section of their return, rather than having to enter it manually.