How to Calculate Your Tax Bill as a UK Freelancer in 2026

Why Freelancers Struggle with Tax

Unlike employees, freelancers don't have an employer automatically deducting tax through PAYE. That means every payment you receive is gross income — and a chunk of it belongs to HMRC. Getting this wrong can mean a shock bill in January, or worse, penalties for underpayment.

The good news is that once you understand the structure, calculating your approximate tax bill is straightforward. This guide walks through the key components for the 2026/27 tax year.

Step 1: Calculate Your Taxable Profit

Your tax is based on profit, not turnover. Start with your total income from freelance work, then subtract allowable business expenses (software subscriptions, professional development, home office costs, etc.).

For example: if you earned £60,000 and had £8,000 in expenses, your taxable profit is £52,000.

Step 2: Apply the Personal Allowance

Every UK taxpayer gets a Personal Allowance — the amount you can earn tax-free. For 2026/27 this remains £12,570. So from our £52,000 profit, the first £12,570 is tax-free, leaving £39,430 subject to tax.

Note: if your income exceeds £100,000, the Personal Allowance is tapered away at £1 for every £2 above that threshold.

Step 3: Calculate Income Tax

Income Tax is applied in bands to your income above the Personal Allowance:

• Basic rate (20%): £12,571 to £50,270
• Higher rate (40%): £50,271 to £125,140
• Additional rate (45%): Over £125,140

Using our example: £39,430 falls entirely within the basic rate band, so Income Tax = £39,430 × 20% = £7,886.

Step 4: Add National Insurance

Self-employed people pay Class 4 National Insurance on profits above £12,570. For 2026/27 the rates are:

• 9% on profits between £12,570 and £50,270
• 2% on profits above £50,270

On £52,000 profit: (£50,270 − £12,570) × 9% = £3,393, plus (£52,000 − £50,270) × 2% = £34.60. Total NI = £3,427.60.

Class 2 NI (a flat weekly rate) was abolished from April 2024, so most sole traders no longer pay it separately.

Step 5: Total Your Tax Bill

Income Tax (£7,886) + Class 4 NI (£3,428) = approximately £11,314 on £52,000 profit. That's an effective rate of around 21.8%.

How Much to Set Aside Each Month

A common rule of thumb is to save 25–30% of every payment you receive. This covers Income Tax, National Insurance, and gives a small buffer for unexpected costs. If your profits are consistently higher (over £50,000), consider setting aside 35%.

Payment on Account

HMRC requires most self-employed people to make payments on account — advance payments towards next year's tax bill, due in January and July. Each payment is 50% of last year's bill. Factor this into your cash flow planning.

Use a Tool to Track It in Real Time

Rather than doing this calculation manually at year end, tools like Beancountr calculate your running tax reserve automatically as income comes in. You always know exactly what's set aside, and there are no January surprises.