Sole Trader vs Limited Company: Full Tax Comparison (2025/26)
Should you incorporate? The answer depends on your profit level, how much you need to extract, and your tolerance for admin. Here's the definitive tax comparison.
The Fundamentals
| Sole Trader | Limited Company | |
|---|---|---|
| Legal status | You and the business are one | Separate legal entity |
| Tax on profits | Income tax + Class 4 NI | Corporation tax (19-25%) |
| Extracting money | It's all yours | Salary + dividends + pension |
| Filing | Self Assessment (SA100) | CT600 + Self Assessment |
| National Insurance | Class 4 (6%/2%) | Employer + Employee NI on salary only |
| Liability | Unlimited personal liability | Limited to company assets |
Note on Class 2 NI: From 6 April 2024, Class 2 National Insurance was abolished for self-employed people with profits above the small profits threshold. It no longer applies and is not included in any calculation below. Voluntary contributions remain available at £3.50/week to protect your NI record.
Tax Comparison at Key Profit Levels
All figures use 2025/26 rates. The limited company scenarios assume a salary of £12,570 (using the full personal allowance) plus dividends. An important change from April 2025: employer NIC rose to 15% above a £5,000 secondary threshold, and sole-director companies where the only paid employee is the director cannot claim Employment Allowance. That means a £12,570 salary costs the company approximately £1,136 in employer NIC every year — which significantly narrows the tax advantage at lower profit levels.
£25,000 Profit
Sole Trader:
- Income: £25,000
- Personal allowance: -£12,570
- Taxable: £12,430
- Income tax (20%): £2,486
- Class 4 NI (6% on £12,570–£25,000): £746
- Total tax: £3,232 (12.9%)
Limited Company (salary £12,570 + dividends):
- Employer NIC on salary: (£12,570 − £5,000) × 15% = £1,136 (no Employment Allowance for sole-director companies)
- Company profit after salary and employer NIC: £11,294
- Corporation tax at 19%: £2,146
- Available for dividends: £9,148
- Personal dividend tax: (£9,148 − £500 allowance) × 8.75% = £757
- Total tax: £4,039 (16.2%)
Sole trader is cheaper by ~£807 at this level. The employer NIC on the director's salary adds £1,136 to the company's costs, which more than wipes out any corporation tax benefit at this profit level.
£50,000 Profit
Sole Trader:
- Personal allowance: -£12,570
- Taxable: £37,430
- Income tax (20%): £7,486
- Class 4 NI (6% on £12,570–£50,000): £2,246
- Total tax: £9,732 (19.5%)
Limited Company (salary £12,570 + dividends):
- Employer NIC: £1,136
- Company profit after salary and employer NIC: £36,294
- Corporation tax at 19%: £6,896
- Available for dividends: £29,398
- Dividend tax: (£29,398 − £500) × 8.75% = £2,529
- Total tax: £10,561 (21.1%)
Sole trader is still cheaper by ~£829. Even at £50,000 profit, the employer NIC cost means the limited company structure costs more in total tax — unless you make pension contributions or retain significant profits in the company rather than extracting them.
£75,000 Profit
Sole Trader:
- Basic rate tax (20% on £12,571–£50,270): £7,540
- Higher rate (40% on £50,271–£75,000): £9,892
- Class 4 NI: £2,262 + £495 = £2,757
- Total tax: £20,189 (26.9%)
Limited Company (salary £12,570 + dividends):
- Employer NIC: £1,136
- Company profit after salary and employer NIC: £61,294
- Corporation tax at 19%: £11,646
- Available for dividends: £49,648
- Dividend tax: basic rate portion ~£37,200 at 8.75% = £3,255; higher rate portion ~£11,948 at 33.75% = £4,032
- Total tax: £20,069 (26.8%)
Essentially breakeven — Ltd saves about £120 (0.2%). This is the approximate crossover for full extraction without any pension contributions.
£100,000 Profit
Sole Trader:
- Basic rate: £7,540
- Higher rate (40% on £50,271–£100,000): £19,892
- Class 4 NI: £2,262 + £995 = £3,257
- Total tax: £30,689 (30.7%)
Limited Company (salary £12,570 + dividends, full extraction):
- Employer NIC: £1,136
- Company profit after salary and employer NIC: £86,294
- Corporation tax (marginal relief applies): ~£19,118
- Available for dividends: ~£67,176
- Dividend tax: basic rate £3,255 + higher rate £9,948 = £13,203
- Total tax: ~£33,457 (33.5%)
If you extract everything as dividends, the sole trader pays less at £100,000. But the limited company wins decisively if you:
- Leave money in the company (only pay 19–25% corp tax, defer personal tax)
- Use employer pension contributions (deductible, no NI)
- Claim expenses more efficiently
With pension optimisation:
- Employer pension contribution: £30,000
- Corp tax saving: £30,000 × 25% = £7,500
- NI saving: £30,000 × 15% = £4,500
- Reduces dividends needed, lowering personal tax
Revised total tax with pension: ~£18,000–£20,000 (18–20%)
£150,000 Profit
At this level, the limited company advantage is clear:
Sole Trader: ~£58,000 tax (38.7%) Limited Company (optimised with pension): ~£33,000–£35,000 (22–23%)
Saving with Ltd: ~£23,000–£25,000
The Crossover Point
The employer NIC changes from April 2025 — rate up to 15%, secondary threshold down to £5,000 — significantly affect the calculation. A sole-director company paying a £12,570 salary now incurs ~£1,136/year in employer NIC with no relief from Employment Allowance.
Once these costs are properly counted, the breakeven point where a limited company offers a meaningful tax saving (full extraction, no pension) is around £70,000–£80,000 profit. Pension contributions bring this crossover lower for those who can lock money away until retirement.
When you include the annual costs of running a company:
- Accountancy fees: £500–£1,500/year
- CT600 filing: £59 with Taxpipe
- Companies House confirmation statement: £50/year
- Payroll admin: £100–£300/year
The true financial crossover after all costs depends heavily on whether you make pension contributions. Without them, expect the breakeven to sit above £80,000 profit. With regular employer pension contributions, the advantage can emerge at a lower level.
Beyond Tax: Other Reasons to Incorporate
Limited liability
As a sole trader, you're personally liable for all business debts. A limited company protects your personal assets (house, savings, car).
Professional credibility
Some clients — especially larger companies — prefer to work with limited companies. It can affect whether you win contracts.
IR35 considerations
If you're a contractor, operating through a limited company is the standard structure. Being a sole trader may limit your contract options.
Pension contributions
Employer pension contributions from a company are:
- A deductible company expense
- Not subject to NI
- Subject to the £60,000 annual allowance (employer and personal contributions are tested together against this limit)
This is the single biggest tax advantage of a limited company, particularly at higher profit levels.
Retained profits
A company can retain profits at the corporation tax rate (19–25%) and reinvest them. A sole trader pays income tax + NI on all profits regardless of whether they need the money personally.
Why Some People Stay Sole Traders
Simplicity
No Companies House filings, no CT600, no payroll, no dividend paperwork. Just a Self Assessment return once a year.
Cash flow
All business profits are immediately accessible. No need to declare dividends or process payroll.
Privacy
Sole trader accounts aren't public. Limited company accounts are filed at Companies House and visible to anyone.
Lower admin costs
No accountant needed for many sole traders. No filing fees. No annual confirmation statements.
Loss relief flexibility
Sole traders can offset business losses against other personal income (employment, rental, etc.) more easily than company losses.
The Optimal Company Setup
If you decide to incorporate, the most tax-efficient structure for most small companies:
Salary: £12,570
- Uses the personal allowance (no income tax)
- Deductible for corporation tax
- Employer NIC applies: ~£1,136/year (sole-director companies cannot claim Employment Allowance)
Employer pension: Up to the annual allowance
- Fully deductible for the company
- No NI on employer contributions
- Both employer and personal pension contributions count toward the £60,000 annual allowance combined
Dividends: The rest
- 8.75% basic rate (much less than 40% income tax)
- £500 tax-free dividend allowance
- Declare only what you need — leave the rest in the company
What NOT to do
- ❌ Pay yourself a large salary (triggers employer + employee NI)
- ❌ Extract everything as dividends (may trigger higher rate)
- ❌ Forget to declare dividends (HMRC can challenge this)
- ❌ Mix personal and business money (creates director's loan problems)
Making the Switch: Incorporation
If you decide to incorporate:
- Register at Companies House (£100 online, same day)
- Register for Corporation Tax within 3 months
- Open a business bank account
- Transfer assets from sole trader to company (may have tax implications)
- Close your sole trader Self Assessment (or keep it if you have other personal income)
- Set up payroll (even if just for your small salary)
- File your CT600 when due — Taxpipe makes it easy at just £59
Frequently Asked Questions
Can I be a sole trader AND a company director?
Yes. You can have a limited company for one business and be a sole trader for another. Each has its own tax return.
What about the flat rate VAT scheme?
Available to both sole traders and limited companies. The 16.5% limited cost trader rate applies mainly to service businesses with low costs.
Is it expensive to switch from sole trader to limited company?
Companies House registration is £100. The main costs are ongoing: accountancy, CT600 filing (£59 with Taxpipe), and admin time.
Can I switch back from limited company to sole trader?
Yes, through disincorporation — but it can trigger capital gains and tax charges on the transfer of assets. Get advice before switching back.
At what profit level do you recommend incorporating?
With 2025/26 employer NIC rates, a limited company starts to show a meaningful tax saving (full extraction, no pension) at around £70,000–£80,000/year profit. If you make significant employer pension contributions, the crossover can come earlier. Below those levels, the tax saving is minimal or negative once employer NIC is factored in.
Already running a limited company? File your CT600 with Taxpipe — £59, no subscription, guided step-by-step. The simplest replacement for HMRC's free filing tool.