Most business owners ask this question at some point. The honest answer is: it depends on your profit level, risk tolerance, and future plans. Here's a factual comparison to help you decide.
The key differences at a glance
| Factor | Sole Trader | Limited Company |
|---|---|---|
| Setup | Register with HMRC only | Incorporate at Companies House |
| Personal liability | Unlimited (you = the business) | Limited to your shareholding |
| Tax on profits | Income tax + Class 4 NI | Corporation tax (19–25%) |
| Take-home income | Profit after income tax/NI | Salary + dividends (more control) |
| Admin burden | Low | Higher (accounts, CT600, confirmation statement) |
| Privacy | No public register | Accounts are public at Companies House |
| Raising investment | Difficult | Easier (issue shares) |
| Credibility | Lower in some industries | Higher in some industries/contracts |
The tax comparison - where the numbers matter
The most common reason to incorporate is tax efficiency. Here's a simplified comparison at different profit levels (2024/25 rates, single person, no other income, taking maximum dividends):
At £20,000 profit
Sole trader: income tax £1,486 + Class 4 NI £685 = ~£2,171 tax. Take-home: ~£17,829.
Limited company: corporation tax on profits + income tax on salary/dividends - roughly similar or slightly less efficient once you include accountancy costs. The saving doesn't justify the extra admin at this level.
At £40,000 profit
Sole trader: income tax ~£5,486 + Class 4 NI ~£2,185 = ~£7,671. Take-home: ~£32,329.
Limited company: with optimal salary/dividend structure, effective tax often £3,000–£4,500 less. The saving starts to clearly outweigh the accountancy cost difference (~£600–£900/year extra for Ltd vs sole trader accounting).
At £60,000+ profit
The gap widens significantly. Corporation tax at 25% (with small profits relief between £50k–£250k) combined with dividend rates (8.75% basic rate) versus income tax at 40% + NI means the benefit of a limited company becomes substantial. Most advisers agree incorporation is clearly worthwhile at this level.
Liability: the non-tax reason to incorporate
As a sole trader, you and your business are legally the same entity. If your business is sued or can't pay a debt, your personal assets - your home, savings, car - are at risk.
A limited company is a separate legal entity. Your liability is generally limited to your shareholding (the value you paid for your shares, often £1). This doesn't protect against personal guarantees or fraud, but for normal trading risk, incorporation provides a meaningful shield.
If you're in a sector where claims are possible (construction, professional services, tech, consulting), this matters.
The admin reality of a limited company
A limited company requires more work than a sole trader setup:
- Annual accounts filed at Companies House
- Corporation tax return with HMRC
- Director's self assessment (yes, even with a Ltd company)
- Monthly RTI payroll if paying a salary
- Quarterly VAT returns (if registered)
- Annual confirmation statement
That said, with a fixed-fee accountant, all of this is handled for you. The decision of whether to incorporate isn't really about your personal admin - it's about the tax and liability picture.
When is the right time to incorporate?
There's no single answer, but common triggers:
- Your profit reaches roughly £30,000–£40,000/year and you don't need to draw all of it immediately
- You want to limit personal liability
- You're signing contracts that require a Ltd company
- You want to bring in investors or business partners
- You're planning to grow and hire
The key phrase in the tax calculation is "profit you don't need to draw immediately." If you need every pound of your profit to live on, a Ltd company offers less benefit - you'll pay more income tax on dividends once you've taken everything out. If you can leave some profit in the company, the tax deferral compounds over time.
Still not sure?
Tell us your rough profit level and whether you'd need to take it all out, and we'll give you a straight answer on whether incorporation is likely to save you money. Book a free call →