How to Register as Self-Employed with HMRC: A Tradesperson's Guide

Written by Tom Ellis · Senior Trades Editor

Last updated: 9 November 2026

Quick Answer

You must register as self-employed with HMRC by 5 Octoberin the second tax year after you started working self-employed. So if you started in the 2026–27 tax year, your registration deadline is 5 October 2027. Registering late means you'll still owe tax and National Insurance from day one — plus a potential fine.

Registration is free and takes about 10–15 minutes online via GOV.UK. You'll need your National Insurance number and a Government Gateway account.

When do you need to register?

HMRC's rule is straightforward: you must register as self-employed by 5 October following the end of the tax year in which you started trading. The UK tax year runs from 6 April to 5 April.

When you started	Tax year	Registration deadline
Any date in 2025–26	2025–26 (6 Apr 2025 – 5 Apr 2026)	5 October 2026
Any date in 2026–27	2026–27 (6 Apr 2026 – 5 Apr 2027)	5 October 2027
Any date in 2027–28	2027–28 (6 Apr 2027 – 5 Apr 2028)	5 October 2028

There is no minimum earnings threshold for registering — you must register as soon as you start trading, even if you haven't invoiced anyone yet. The only exception is if your total self-employment income for the year stays below the £1,000 trading allowance — in that case you have no tax to pay and don't need to register or file a tax return.

Don't wait until you're busy

Many tradespeople delay registering because they're not earning much yet. This is a mistake — HMRC charges a penalty for late registration and will still want tax and National Insurance from the date you started. Register early and you won't owe a lump sum later.

What you need before you register

✓
National Insurance number: Your NI number is on your payslips, P60, or any HMRC letter. If you've lost it, contact HMRC on 0300 200 3500.
✓
Government Gateway user ID and password: If you don't have one, you'll create it during the registration process. You'll need an email address and a form of ID (passport, driving licence, or payslip).
✓
Start date of self-employment: The date you started trading — not when you registered the business or opened a bank account, but when you first did paid work or were ready to accept it.
✓
Nature of your trade: A simple description: 'electrician', 'plumber', 'builder', etc. You'll also be asked for the Standard Industrial Classification (SIC) code for your trade.
✓
Home address and phone number: HMRC sends correspondence to your registered address. You can use your home address.

Step-by-step: how to register online

Go to GOV.UK

Go to gov.uk and search "register self-employed", or go directly to the "Register for Self Assessment" page. HMRC's registration journey starts there — don't use a third-party site.

If you already file VAT or CIS through the Government Gateway, use the same account. Otherwise create a new one — you'll need a valid email address and to verify your identity using a form of ID.

Tell HMRC you're self-employed

Select "I want to tell HMRC about a new source of income" and then "Self-employment (sole trader)". If you also receive property income, select that too.

Enter your personal and trade details

Fill in your name, address, NI number, start date and type of business. HMRC will ask for your trade and assign a SIC code.

Submit

Review and submit. HMRC will confirm receipt immediately. Within 10 working days you'll receive your Unique Taxpayer Reference (UTR) number by post — keep this safe.

Activate your Self Assessment account

When your UTR arrives, return to the Government Gateway and activate your Self Assessment account using the activation code HMRC sends. You need this before you can file a tax return.

What happens after you register

Once registered, HMRC enrolls you in Self Assessment. Each year you must file a Self Assessment tax return covering the previous tax year (6 April to 5 April). The deadline for online filing is 31 January — both for the return and any tax owed.

You also become liable for Class 4 National Insuranceon your profits (9% on profits between £12,570 and £50,270; 2% above). If your profits are under £6,725, there's no NI to pay; between £6,725 and £12,570, you get a notional NI credit (protecting your State Pension entitlement) without paying anything extra.

If you're in the Construction Industry Scheme (CIS), you'll also need to register with HMRC as a CIS subcontractor separately. See our CIS subcontractor guide.

If you become VAT registered (mandatory once your turnover exceeds £90,000, or optional below that), you need to register for VAT separately — it's not part of the Self Assessment process.

Payments on account — the surprise bill

One thing that catches many tradespeople out in their first year: payments on account. When you file your first Self Assessment return, HMRC may ask you to pay not only the tax you owe for the past year, but also an advance payment towards the current year — typically 50% of last year's bill, due in January, then another 50% the following July.

This means your first tax bill can be up to 150% of what you expected. Plan for this by putting aside 25–30% of every payment you receive into a separate savings account as you go.

What if you're already late registering?

Register now — the sooner you do, the smaller the potential penalty. HMRC charges a failure-to-notify penalty, calculated as a percentage of the tax you would have paid if you'd registered on time. The penalty is reduced if you tell HMRC before they find out themselves.

If you've been trading for a while without registering, you'll need to file tax returns for all the years you should have — but HMRC will only normally go back six years from the current date. Contact HMRC proactively; they tend to be more lenient with people who come forward than those they catch.

Registration FAQs

Do I need to register a business name?

No. As a sole trader, you can trade in your own name without registering a business name anywhere. If you want to trade under a different name (e.g. 'JB Plumbing Services' rather than your personal name), you can do so without formal registration — just make sure your legal name appears on invoices. You cannot use 'Limited' or 'Ltd' in a sole trader name.

I'm an employee but I also do weekend jobs. Do I need to register?

Yes, if your self-employment income is more than £1,000 in a tax year. You can still be employed elsewhere — being an employee doesn't stop you being self-employed simultaneously. HMRC deals with both through the same Self Assessment return.

I'm a CIS subcontractor. Is registering for CIS the same as registering as self-employed?

No. CIS registration and self-employment registration are separate processes. You can register for CIS (which affects the tax rate your contractor deducts) independently of Self Assessment. Most self-employed CIS subcontractors need to do both.

Can I register by phone instead of online?

Yes. Call HMRC Self Assessment helpline on 0300 200 3310. Have your NI number, start date and trade details ready. The online route is faster and you get immediate confirmation, but phone registration is an option if you prefer.

Do I need a business bank account?

HMRC doesn't require it, but it's strongly recommended. Keeping your business and personal finances separate makes bookkeeping far easier, helps if HMRC ever queries your records, and gives you a clearer picture of how the business is performing.

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