Limited company vs sole trader UK: how to set up either

You’ve decided to start working for yourself. Maybe it’s freelance design work, a trades business, consulting on the side, or finally turning that Etsy shop into something real. And now you’re stuck on a question that sounds simple but isn’t: should you register as a sole trader, or set up a limited company?

This decision gets made too quickly, too often. People pick “limited company” because it sounds more professional, or “sole trader” because it sounds easier — without actually working out which one saves them money or protects them better. Both are valid. Which one is right depends on how much you expect to earn, how much risk you’re carrying, and how much admin you can stomach.

This article walks through what each structure actually means, how to set one up, and the tax and liability differences that should genuinely drive your decision — not guesswork.

What’s the actual difference?

A sole trader is you, trading under your own name (or a business name), with no legal separation between you and the business. The business’s profits are your income. Its debts are your debts.

A limited company is a separate legal entity. It’s registered at Companies House, has its own finances, and you — as a director — are typically an employee of it, even if you’re the only person involved. The company owns the profits until it pays them out to you, usually as salary and dividends.

The practical consequence of this split matters more than people expect:

• Liability: As a sole trader, if the business can’t pay its debts, creditors can come after your personal assets — your savings, potentially your house, depending on the debt. With a limited company, your personal liability is generally limited to what you’ve invested in the company (hence the name). This is the main reason tradespeople, consultants with contracts, and anyone taking on business debt or risk often lean towards a limited company.
• Tax: Sole traders pay Income Tax and Class 2/Class 4 National Insurance on all their profits. Limited company directors pay Corporation Tax on company profits, then Income Tax and National Insurance only on what they actually draw out as salary or dividends — which opens up more ways to structure how you get paid.
• Perception: Rightly or wrongly, some clients and suppliers take a limited company more seriously, particularly for B2B work or larger contracts.

The misconception: “limited company always saves you tax”

This is the one that trips people up. It’s not automatically true, and at lower income levels it’s often false.

Running a limited company means running payroll, filing a Corporation Tax return, filing annual accounts with Companies House, and usually paying an accountant to keep it all straight — typically a cost of hundreds to over a thousand pounds a year depending on complexity. Below a certain profit level (often cited as somewhere around £30,000–£40,000, though this shifts with tax rules and your personal circumstances), the extra admin and accountancy costs can eat up most or all of the tax saving.

The tax advantage of a limited company tends to kick in as profits grow, because you can leave money in the company and only draw out what you need, rather than being taxed on every pound of profit the moment you earn it. If you’re earning modestly and need to take out most of your profit to live on anyway, that flexibility matters less.

There’s no single income threshold where this flips — it depends on your other income, your expenses, and how much you need to withdraw. This is genuinely one of the few areas where paying for half an hour with an accountant before you register anything can be worth more than hours of reading guides online.

Setting up as a sole trader

This is the simpler of the two, and for many people starting out, it’s the sensible first step.

1. Register with HMRC as self-employed, by 5 October in your business’s second tax year of trading. You do this by registering for Self Assessment at gov.uk.
2. Keep records of your income and expenses from day one — you’ll need these for your tax return.
3. File a Self Assessment tax return every year, and pay Income Tax and National Insurance on your profits by the 31 January deadline (with a second payment on account sometimes due in July).
4. Register for VAT if your turnover exceeds the VAT threshold, or voluntarily if it suits your business.
5. Get appropriate insurance — public liability or professional indemnity, depending on your work — since there’s no corporate shield protecting you.

That’s it. No Companies House filing, no separate business bank account requirement (though it’s strongly recommended), no annual accounts in the formal sense.

Setting up a limited company

More steps, more structure, but more protection and more flexibility once you’re established.

1. Choose a company name that isn’t already taken and meets Companies House naming rules.
2. Register the company at Companies House — this costs a small fee (typically under £50 online) and can usually be done within 24 hours.
3. Appoint at least one director (you, probably) and decide on shareholders — again, often just you.
4. Set up a business bank account — this is a legal requirement in practice, since company money must be kept separate from personal money.
5. Register for Corporation Tax with HMRC within three months of starting to trade.
6. Run payroll if you’re paying yourself a salary, and register as an employer with HMRC if needed.
7. File annual accounts and a Confirmation Statement with Companies House every year, and a Corporation Tax return with HMRC.
8. Keep company and personal finances strictly separate — this is non-negotiable and the single most common mistake new directors make.

Most people setting up a limited company use an accountant from day one, because the compliance burden is heavier and mistakes are more costly to unwind than with sole trader status.

Side-by-side comparison

Can you switch later?

Yes, and plenty of people do. A common path is starting as a sole trader to test whether the business works, then incorporating (becoming a limited company) once profits grow enough to justify the extra admin and the tax structure starts to pay off. Switching involves registering the new company, transferring business assets and contracts across, and closing down the sole trader registration — it’s manageable, but it’s not instant, and there are tax implications to transferring assets into a company that are worth checking with an accountant first.

There’s no penalty for starting simple. The bigger mistake is incorporating too early, before there’s enough profit to justify the cost, just because it “sounds more legitimate.”

What about IR35 and contractor work?

If you’re doing contract work through a limited company — particularly for a single client who effectively controls how, when, and where you work — you may fall under IR35 rules, which determine whether HMRC treats you as genuinely self-employed or as a “disguised employee” for tax purposes. This affects how you can be paid and taxed. It’s a separate and genuinely complex area, and if you’re contracting through a limited company for one main client, it’s worth understanding your IR35 status specifically — MoneyHelper and HMRC’s own guidance are good starting points before you assume limited company status alone protects your tax position.

The bottom line

• Start with your numbers, not your gut. If your expected profit is modest and fairly stable, sole trader is simpler and cheaper to run — you can always switch later.
• If you’re taking on real financial or legal risk — large contracts, debt, physical work with injury risk — the liability protection of a limited company is worth serious consideration even at lower income.
• Get a specific answer on the tax question before you register anything. A short paid consultation with an accountant, using your actual expected income, will tell you more than any general guide — including this one.
• Whichever you choose, separate your business and personal money immediately. Open a dedicated account from day one; it makes your tax return, your accountant’s job, and your own sanity far easier.
• Don’t let “sounding professional” drive the decision. Clients care about reliability and quality of work far more than your company structure.

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