Self Assessment Tax Calculator
Estimate your income tax and National Insurance for the 2024/25 tax year. Enter your gross self-employment income and allowable expenses to get a breakdown of your tax liability and estimated take-home pay.
This is an estimate only — always consult a qualified accountant for your actual tax return.
Frequently asked questions
Who needs to submit a self-assessment tax return?
You must submit a self-assessment return if you are self-employed (even as a sole trader), a partner in a business partnership, a company director, or have other untaxed income (such as rental income or savings interest) above the relevant thresholds. HMRC requires you to register by 5 October of the tax year following the one you need to report.
What income tax rates apply to self-employed income in 2024/25?
For England, Wales and Northern Ireland: the personal allowance is £12,570 (income below this is tax-free); the basic rate of 20% applies to income from £12,571 to £50,270; the higher rate of 40% applies from £50,271 to £125,140; and the additional rate of 45% applies above £125,140. Note that the personal allowance is tapered by £1 for every £2 of income above £100,000.
What National Insurance do self-employed people pay?
Self-employed people pay two classes of NI: Class 2 NI is a flat rate of £3.45 per week if your profits are above the Small Profits Threshold (£12,570 for 2024/25). Class 4 NI is 9% on profits between £12,570 and £50,270, and 2% on profits above £50,270. Note: from April 2024 Class 2 is being abolished for many self-employed people.
How do I reduce my self-assessment tax bill?
The most effective way is to claim all legitimate business expenses — tools and equipment, vehicle costs (mileage or actual costs), home office costs, professional subscriptions, training, insurance, and more. Keeping accurate records of expenses throughout the year using software like InvoiceAdept makes this much easier at tax time.
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Track your income and expenses all year round
InvoiceAdept lets you track invoices and expenses in one place, so self-assessment time is just a download away — not a month of spreadsheet panic.
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