Inside IR35 vs Outside IR35 Guide | Contractor Take-Home Pay

Quick answer

Inside IR35 is usually taxed more like employment income, often through PAYE or an umbrella-style payroll. Outside IR35 usually means a genuine business-to-business engagement, often through a limited company.

The comparison is not just tax rates. It also depends on whether the inside IR35 rate is worker gross pay or an assignment rate before employer-side costs.

Worked example: £500/day for 46 weeks

A contractor on £500 per day, 5 billable days per week and 46 working weeks has headline annual assignment revenue of £115,000 before any tax or costs.

If that £500/day is worker gross taxable pay, the inside IR35 calculation starts from a much higher worker pay figure than if the same £500/day has to fund employer National Insurance, apprenticeship levy and umbrella/admin margin first.

Outside IR35, the same £115,000 is company revenue. Business expenses, director salary, employer pension contributions, corporation tax, dividends and dividend tax all affect personal take-home.

Practical explanation

Inside IR35 does not automatically mean the contractor has employment rights. It is mainly a tax treatment for the engagement.

Outside IR35 does not mean tax-free income. It normally means company income is handled through company accounts, then extracted through salary, dividends or pension contributions.

The most useful comparison starts with a realistic annual revenue figure. Day rate, billable days, unpaid weeks, sickness, holidays and gaps between contracts all matter.

Common mistakes

Comparing an outside IR35 company rate with an inside IR35 assignment rate as if both are worker gross pay.

Ignoring umbrella/admin fees, employer-side costs, holiday pay treatment or pension deductions on inside IR35 payslips.

Treating the calculator result as an IR35 status decision. Status depends on the contract and actual working practices.

Try the calculator

Use the related calculator to test the numbers against your own assumptions.

Inside IR35 vs Outside IR35 Calculator

Disclaimer

This guide explains pay mechanics only. It does not decide IR35 status and is not legal, tax, payroll or accountancy advice.

Frequently asked questions

Does inside IR35 mean I am an employee?

Not automatically. Inside IR35 is a tax treatment for an engagement. Employment rights, benefits and legal employment status are separate questions.

Why can an inside IR35 rate be hard to compare?

Some inside IR35 rates are quoted as worker gross pay, while others are assignment rates before employer-side costs and umbrella fees. The basis matters before comparing take-home pay.

Does outside IR35 always give higher take-home pay?

No. Outside IR35 can be more flexible, but company profit, corporation tax, dividends, expenses, pension choices and retained profit all affect the result.

Does a calculator decide IR35 status?

No. IR35 status depends on the contract and actual working practices. A calculator can compare pay scenarios, but it cannot review control, substitution, mutuality of obligation or wider status factors.

Should umbrella company figures match exactly?

No. Umbrella payslips can vary because of holiday pay treatment, pension rules, employer National Insurance, apprenticeship levy, provider margin and agency arrangements.

Related calculators and guides

Inside IR35 vs Outside IR35 CalculatorCompare contractor take-home inside and outside IR35.UK Contractor Day Rate CalculatorCompare sole trader and limited company take-home scenarios.Director Salary & Dividend CalculatorEstimate personal take-home from a limited company salary and dividends.UK Dividend Tax CalculatorEstimate dividend tax based on salary, other income and dividends.Contractor Day Rate vs SalaryCompare contractor rates with employee salary in a practical way.