How to register as self-employed or a sole trader: a tradesperson's guide

"Self-employed" describes how you work: for yourself, taking on the risk and the profit, rather than as someone's employee. "Sole trader" describes the legal structure of the business itself: one person trading in their own name (or a trading name), with no legal separation between them and the business. Someone who is self-employed and trading as a sole trader, rather than through a limited company, is both at once.

The two terms lead to exactly the same registration. There's no separate "register as self-employed" form and "register as a sole trader" form; you register for Self Assessment once, and that single registration covers both. Search either phrase on GOV.UK and you land on the same registration route.

This is different from being a limited company director, which is a distinct legal and tax structure with its own registration through Companies House and Corporation Tax. This page is about the sole trader / self-employed route specifically.

Yes, if your gross trading income (everything you're paid before any expenses) is more than £1,000 in a tax year (6 April to 5 April). This is HMRC's trading allowance threshold: cross it, and you must register for Self Assessment, whether or not you actually end up owing tax once expenses are deducted.

You may still need to register even under £1,000 in some situations: for example, if you want to pay voluntary Class 2 National Insurance to protect your State Pension record, if you need to prove you're self-employed (for Tax-Free Childcare or similar), or if you need to register as a CIS subcontractor. If none of those apply and your income is £1,000 or less, you generally don't need to tell HMRC at all.

If you've registered for Self Assessment before for a different reason (rental income, for example) but haven't previously registered as self-employed specifically, you still need to register again as a sole trader. That's a separate step even though you already have a Self Assessment account, because it's what triggers Class 2 National Insurance.

None of this needs an accountant to gather. If you already have a Government Gateway account from a previous tax return or another government service, sign in with that one rather than creating a new one, where the registration service directs you to.

• ▸Your National Insurance number.
• ▸Your personal details: full name, date of birth, address, contact details.
• ▸Details of the business: what the work is, the trading name if you're using one, and the date you started self-employment.
• ▸A Government Gateway user ID and password: the service creates one for you if you don't already have one.
• ▸If you're also registering as a CIS subcontractor: see the CIS section below, since it changes one step in the process.

There's no fee to register for Self Assessment or CIS. Registration itself is free; what changes is your ongoing tax and National Insurance position once you're trading.

• ▸1. Go to GOV.UK's "Check how to register for Self Assessment" and confirm which route applies to you: first-time registration, or reactivating a lapsed account.
• ▸2. Follow the link through to register online. If you don't have a Government Gateway account, you create one as part of this step.
• ▸3. Complete the online form with your personal and business details, including the date your self-employment started.
• ▸4. If you do construction work for a contractor, select the option for registering as a subcontractor at this point, so Self Assessment and CIS are registered together rather than as two separate applications later.
• ▸5. Submit the registration. HMRC processes it and posts your ten-digit Unique Taxpayer Reference (UTR) to your registered address, then activates your online Self Assessment account.
• ▸6. Once you have your UTR and account access, you can file returns, make payments and, if relevant, verify with contractors for CIS.

If you'll be doing construction work for a contractor rather than working directly for the public, you're a CIS subcontractor, and registering matters immediately, not eventually: it decides how much tax is deducted from every payment you receive before you've filed a single tax return.

Registered subcontractors have 20% deducted from the part of their payment that's subject to CIS, as an advance towards tax and National Insurance; unregistered subcontractors have 30% deducted instead. That CIS-deductible amount excludes VAT and costs such as materials you've paid for directly, plant hire and consumable stores, so the deduction isn't taken from the whole invoice. You can also apply for gross payment status (0% deducted) at the same time as registering, subject to HMRC's turnover, business and compliance tests.

CIS deductions are not your final tax bill. They're an advance payment, credited against what you actually owe when you file your Self Assessment return, and a refund is paid if the deductions taken turn out to be more than your final liability.

For the full mechanics (how the deduction is calculated, verification, gross payment status and what changed in CIS from April 2026), see TBV's CIS guide, linked below. This page only covers the registration decision.

You'll usually get your Unique Taxpayer Reference by post around 15 days after you register; once it's issued, you can also find it in your Personal Tax Account or the HMRC app. Once your Self Assessment account is active, you're responsible for keeping records of your income and expenses and filing an annual tax return. What you owe depends on your profits: Class 4 National Insurance only applies above £12,570 of profit; at or above £7,105 of profit, Class 2 is treated as paid and no Class 2 payment is due, and below £7,105 you can choose to pay Class 2 voluntarily.

Registering doesn't create an immediate bill. Nothing is owed until you file your first return and HMRC calculates what you actually owe based on your real income and expenses for the year, not the fact that you've registered.

If you stop trading, tell HMRC. Don't just let the registration lapse: leaving it un-notified can mean HMRC continues expecting returns from a business that no longer exists.

Register after 5 October and don't pay your full tax bill by 31 January, and HMRC can charge a failure-to-notify penalty based on the amount you still owe. Register as soon as you know you're over the threshold rather than waiting for the deadline to approach, so you're not relying on paying everything by 31 January to avoid a penalty.

Making Tax Digital for Income Tax doesn't apply the moment you register. It applies once your gross qualifying income (turnover before expenses, not profit) crosses a threshold, on this schedule:

If you're newly self-employed and clearly below all three thresholds, MTD isn't something to act on yet. Just be aware the threshold is scheduled to fall to £20,000 from April 2028, so it's worth checking again as your income grows. See TBV's Making Tax Digital guide, linked below, for exactly what to do once it applies to you.

• ▸Waiting until 5 October to register instead of registering as soon as you cross the £1,000 threshold or know you're trading. Registering late and not paying your full tax bill by 31 January can mean a failure-to-notify penalty, based on what's still outstanding.
• ▸Registering as self-employed but forgetting to also select CIS subcontractor registration, then having 30% instead of 20% deducted from CIS-liable payments until it's fixed.
• ▸Assuming registering creates an immediate tax bill. It doesn't; you're taxed on what your return actually shows, not on the act of registering.
• ▸Creating a second Government Gateway account instead of signing in with an existing one, where the registration service directs you to reuse it.
• ▸Not telling HMRC when trading stops, leaving an open registration that keeps expecting returns.
• ▸Treating the £1,000 trading allowance as automatically tax-free profit rather than as a registration threshold and an alternative to claiming actual expenses. It can be used either way, but not both, and using it isn't automatic.