Self-Employed vs Limited Company: Which Structure Saves You More Tax?

One of the most common questions freelancers, contractors, and small business owners ask is: should I stay self-employed or set up a limited company? The answer almost always comes down to tax.

At lower income levels, being a sole trader is simpler and cheaper. But as your profits grow, the tax savings from operating through a limited company can be substantial — often thousands of pounds per year. This guide breaks down the numbers so you can make an informed decision.

How Self-Employment Tax Works

As a sole trader, your business profits are treated as personal income. You pay:

• Income Tax on your profits (after deducting allowable expenses)
• Class 2 National Insurance — £3.45 per week (2024/25)
• Class 4 National Insurance — 6% on profits between £12,570 and £50,270, plus 2% on profits above £50,270

Your total tax burden is calculated on your entire taxable profit. There is no separation between you and your business.

Example at £50,000 profit:

• Income Tax: £7,486
• Class 2 NI: £179
• Class 4 NI: £2,244
• Total: £9,909 (effective rate: ~19.8%)

How Limited Company Tax Works

A limited company is a separate legal entity. The company pays Corporation Tax on its profits, and then you extract money through a combination of salary and dividends.

The key rates:

• Corporation Tax: 19% (profits under £50,000) or 25% (profits over £250,000), with marginal relief in between
• Dividend Tax: 8.75% (basic rate), 33.75% (higher rate), 39.35% (additional rate)
• Dividend Allowance: £500 tax-free (2024/25)

Most director-shareholders use an optimal strategy: pay a small salary at the National Insurance threshold (around £12,570) and take the rest as dividends.

Example at £50,000 profit (limited company):

• Corporation Tax (19%): £7,117 (on £37,430 profit after £12,570 salary)
• Director salary tax: £0 (below personal allowance)
• Employer NI on salary: £0 (at threshold)
• Dividend tax on £30,313 (post-CT profit): £2,609
• Total: £9,726 (effective rate: ~19.5%)

The saving at £50,000 is modest. But watch what happens at higher income levels.

The Savings Scale With Income

Annual Profit	Sole Trader Tax	Ltd Company Tax	Annual Saving
£30,000	£4,860	£4,515	£345
£50,000	£9,909	£9,726	£183
£75,000	£18,352	£14,643	£3,709
£100,000	£27,432	£20,157	£7,275
£150,000	£46,032	£35,286	£10,746

The crossover point where a limited company clearly wins is typically around £50,000-£60,000 in annual profit. Below that, the additional costs and admin of running a company can outweigh the savings.

National Insurance: The Hidden Difference

National Insurance is where much of the saving comes from. As a sole trader, you pay Class 2 and Class 4 NI on your profits. As a limited company director taking dividends, dividends are not subject to National Insurance at all.

This single difference accounts for the majority of the tax saving at higher income levels.

Pros and Cons Comparison

Factor	Self-Employed	Limited Company
Setup cost	Free	£12-£50 (Companies House)
Annual admin	Self Assessment only	Accounts, CT600, confirmation statement
Accountancy fees	£200-£500/year	£800-£2,000/year
Tax efficiency	Lower at high income	Higher at £50k+ profits
Personal liability	Unlimited	Limited to company assets
Privacy	Personal details private	Public filings at Companies House
Credibility	Perceived as less formal	Perceived as more professional
Money extraction	Take profits freely	Must follow dividend/salary rules
Loss relief	Offset against personal income	Restricted to company
Pension flexibility	Personal contributions only	Employer contributions (more tax-efficient)

IR35: The Contractor Consideration

If you work primarily for one client through a limited company, IR35 legislation may apply. IR35 is designed to prevent "disguised employment" — situations where someone works like an employee but operates through a company for tax advantages.

If HMRC determines your working arrangement falls inside IR35, you will be taxed as if you were an employee, wiping out most of the tax benefits of your limited company.

Key factors HMRC considers:

• Control: Does the client dictate how, when, and where you work?
• Substitution: Could you send someone else to do the work?
• Mutuality of obligation: Is the client obliged to offer work, and are you obliged to accept it?

Since April 2021, medium and large private sector clients are responsible for determining IR35 status. If you are caught inside IR35, remaining self-employed may actually be simpler and no more expensive.

When Should You Switch to a Limited Company?

Consider incorporating when:

• Your annual profits consistently exceed £50,000
• You want to reinvest profits in the business (corporation tax at 19% is lower than income tax)
• You need limited liability protection
• You want to make employer pension contributions (more tax-efficient)
• You are building a business you may want to sell (companies can be sold; sole trader businesses cannot in the same way)

Stay self-employed when:

• Your profits are below £30,000-£40,000
• You value simplicity over tax savings
• You work inside IR35 with most clients
• You want to minimise admin and accountancy costs

The Hidden Costs of a Limited Company

Before you rush to incorporate, factor in:

• Accountancy fees: £600-£1,500 more than sole trader accounts
• Payroll costs: Running payroll for yourself (even if automated)
• Companies House filing: Annual confirmation statement and public accounts
• Banking: Business bank accounts often have monthly fees
• Time: More record-keeping, more compliance, more paperwork

These costs can total £1,000-£2,000 per year, which needs to be deducted from your tax savings calculation.

How TaxDocs Can Help

Whether you operate as a sole trader or a limited company, accurate tax documentation is essential. TaxDocs generates jurisdiction-specific tax documents for both business structures, handling the complexity of corporation tax computations, dividend calculations, and more. Upload your financial data and receive professional documents in minutes — saving you hours of preparation and reducing the risk of costly errors.

The Bottom Line

There is no one-size-fits-all answer. The right structure depends on your income level, working arrangements, risk tolerance, and personal preferences. Run the numbers for your specific situation, factor in all the costs (not just tax), and review your structure annually as your circumstances change.

This article is for informational purposes only and does not constitute tax advice. Always consult a qualified accountant for advice specific to your circumstances.