Self-Employment Registering as Self-Employed UK — Step-by-Step Guide How to register as self-employed with HMRC. Deadlines, what you need, UTR numbers, National Insurance, and everything to get started legally.
20 June 2025
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4 min read
Registering as self-employed is the crucial first step when starting to work for yourself. It is free, straightforward, and ensures you are legally compliant with HMRC from day one.
Who Needs to Register? Situation Need to Register? Selling products or services regularly Yes Freelancing for clientsYes Running any kind of business Yes Trading income over £1,000/year Yes Earning under £1,000/year (Trading Allowance) No Running a limited company Register the company (different process) Landlord with rental income over £1,000Yes (Self Assessment required)
How to Register: Step by Step Step Action Detail 1 Create a Government Gateway account If you do not already have one 2 Register for Self Assessment Online at gov.uk 3 Provide your details NI number, name, address, date of birth 4 Provide business details Business name, type, start date 5 Receive your UTR By post within 10 working days 6 Receive activation code For online access (separate letter) 7 Activate your online account Using the code 8 File your first tax return By 31 January after the tax year
What You Will Need Information Detail National Insurance number On payslips, P60, or HMRC letters Full name and address Current address Date of birth — Phone number and email For HMRC contact Business name Or your own name if trading as yourself Business address Can be your home address Nature of business What your business does Business start date When you started trading
After Registration What You Must Do Obligation Detail Keep records All income and expenses for 5 years File Self Assessment By 31 January (online) or 31 October (paper) Pay Income Tax By 31 January + 31 July (payments on account) Pay National Insurance Calculated on your tax return Register for VAT If turnover exceeds £90,000 Meet MTD requirements Digital records required from April 2026 (income over £50,000)
Key Deadlines Date What 5 October Deadline to register for Self Assessment (in your second tax year) 31 October Paper tax return deadline 31 January Online tax return + first tax payment deadline 31 July Second payment on account
Example Timeline Event Date Start self-employment June 2025 Register with HMRC June 2025 (best) or by 5 October 2026 (deadline) First tax year ends 5 April 2026 File first tax return By 31 January 2027 Pay tax owed By 31 January 2027
Registering for Class 2 National Insurance When you register for Self Assessment, you are automatically registered for Class 2 NI:
NI Class Rate (2025/26) When Payable Class 2 £3.45/week Profits over £12,570 Class 4 6% on £12,570–£50,270 On profits in this band Class 4 (upper) 2% above £50,270 On profits above this
Class 2 NI counts towards your State Pension entitlement — so it is worth paying even if technically voluntary at lower profit levels.
Trading Allowance Detail Amount Allowance £1,000/year What it covers Self-employed income below this threshold Tax return required? No (if total self-employment income is under £1,000) Can you still register? Yes (useful if you want to pay voluntary NI contributions)
Business Structure Choice Structure Register With Pros Cons Sole trader HMRC (Self Assessment) Simple, free, private Unlimited liability Partnership HMRC (SA for each partner) Shared workload Shared liability Limited company Companies House + HMRC Limited liability, tax efficient More admin, public accounts
Additional Registrations Registration When Required VAT Turnover exceeds £90,000 (or voluntary) Employer (PAYE) When you hire employees Construction Industry Scheme (CIS) Working in construction Data Protection (ICO) Processing personal data Local authority licences Depending on trade (food, taxi, etc.)
Common Mistakes Mistake Consequence Not registering at all Penalties + interest on unpaid tax Registering late Potential £100 penalty Not keeping records Difficulty completing tax return, potential HMRC investigation Mixing personal and business finances Messy records, accounting costs Not saving for tax January shock — cannot pay the bill Forgetting payments on account Late payment penalties
Tips for New Self-Employed Workers Register immediately — don’t wait for the deadlineOpen a business bank account — separate your financesStart using accounting software — from day oneSave 25–30% of income for tax from the startGet business insurance if neededConsider an accountant — saves time and often saves taxBuild an emergency fund — there is no employer safety netFor detailed tax information, see our self-assessment guide and tax allowances guide .