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Side Hustle Tax Calculator UK: How Much Tax Will I Pay?

Checked 29 Oct 2026 against GOV.UK · Estimate only, not tax advice

How the side hustle tax calculator works

• Two ways to work out profit. Trading allowance method: your trading income minus the allowance (£1,000 for 2026/27, £3,000 for 2027/28 as announced). Expenses method: your trading income minus your actual allowable costs. GOV.UK says you can use one or the other, not both (GOV.UK: tax-free allowances; expenses if you're self-employed).
• Extra Income Tax. We work out Income Tax on your other income with and without the profit, and show the difference. 2026/27 figures for England, Northern Ireland and Wales: Personal Allowance £12,570; basic rate 20% on the first £37,700 of taxable income; higher rate 40% from £37,701 to £125,140; additional rate 45% over £125,140. The Personal Allowance goes down by £1 for every £2 of income over £100,000, and can go down to zero (GOV.UK: Income Tax rates and allowances; Income Tax rates and Personal Allowances).
• Class 4 National Insurance on the profit alone: for 2026/27, 6% on profits over £12,570 up to £50,270, and 2% on profits over £50,270 (GOV.UK: Self-employed National Insurance rates; Rates and allowances: National Insurance contributions).
• 2027/28. The Budget 2026 rates annex lists the same Personal Allowance (£12,570), £100,000 income limit, 20/40/45% bands (£37,700 and £125,140) and Class 4 limits and rates (£12,570, £50,270, 6% and 2%) for 2027/28 (GOV.UK: Budget 2026 overview of tax legislation and rates, Annex A). The £3,000 trading allowance is from section 1.5, from 6 April 2027, subject to Finance Bill 2026-27 (GOV.UK: Budget 2026 overview of tax legislation and rates). Treat 2027/28 as announced, not final.

How much tax will I pay? Worked examples (2026/27)

We checked these by hand. They're illustrations, not advice.

• £5,000 of sales, £1,800 of costs, £30,000 salary. Allowance method: £4,000 profit, about £800 extra Income Tax at 20%. Expenses method: £3,200 profit, about £640. No Class 4, because the profit is under £12,570. Expenses come out lower.
• £6,000 of sales, £500 of costs, £48,000 salary. Allowance method: £5,000 profit. £2,270 of it fills the rest of the basic rate band up to £50,270 (£454), and £2,730 is taxed at 40% (£1,092): about £1,546. Expenses method: £5,500 profit, about £1,746. Here the allowance comes out lower.
• £20,000 of sales, £4,000 of costs, no other income. Expenses method: £16,000 profit. Income Tax: £3,430 over the Personal Allowance at 20%, £686. Class 4: 6% of £3,430, £205.80. Total about £891.80. The allowance method (£19,000 profit) gives about £1,671.80.

What it doesn't cover

• Scotland. Scottish Income Tax rates and bands are different (GOV.UK: Scottish Income Tax), so this estimate isn't right for Scottish taxpayers.
• Student loans, pensions, savings, dividends, Marriage Allowance, Gift Aid and other reliefs or charges.
• Class 2 National Insurance. GOV.UK says that if your profits are £7,105 or more for 2026/27, Class 2 contributions are treated as paid, so you don't pay them. Below that you can choose to pay voluntarily, at £3.65 a week for 2026/27 (GOV.UK). For 2027/28, the Budget 2026 overview gives a small profits threshold of £7,355 and a voluntary rate of £3.80 a week (GOV.UK: Budget 2026 overview, section 2.1).
• Losses. If your costs are more than your sales, it flags the loss but doesn't work out loss relief.
• Whether you're trading at all. Selling your own unwanted things usually isn't trading. See HMRC's badges of trade and our trading allowance vs expenses guide.

Check the limits first

Not sure you're even over the trading allowance? Our free HMRC limit checker has a tax-year switch for 2026/27 (£1,000) and 2027/28 (£3,000), and shows whether each platform is likely to report you. If you are over it, our Self Assessment guide for resellers covers the deadlines.

Quick answers

Should I use the trading allowance or my actual expenses?

Whichever gives the lower taxable profit. GOV.UK says that if your income is over the allowance you can either deduct the allowance from your income or claim your actual expenses, not both. Resellers who buy stock often have costs above £1,000, so expenses can come out lower. This estimate shows both side by side.

Does this work in Scotland?

No. Scotland has its own Income Tax rates and bands, so this estimate only covers England, Wales and Northern Ireland. Class 4 National Insurance is the same across the UK, but the Income Tax part would be wrong for Scottish taxpayers.

Why does my other income matter?

Your trading profit is added on top of your other income, such as wages. That decides which tax band the profit falls into: the same profit can be taxed at 20%, 40% or 45%, and over £100,000 of income your Personal Allowance starts to go down.

Can I use it for 2027/28?

Yes, as a rough guide. At Budget 2026 the government announced the trading allowance will rise to £3,000 from 6 April 2027, subject to Finance Bill 2026-27. The Budget 2026 rates annex lists the same Personal Allowance, Income Tax bands and Class 4 limits for 2027/28 as for 2026/27. These are announced figures and could change.

Is this my tax bill?

No. It's an estimate only, not tax advice. It ignores student loans, pensions, savings and dividends, losses and other reliefs, and your real bill is worked out through Self Assessment. Check GOV.UK or speak to an accountant.

Not sure where you stand?

• Use HMRC's free tool: Check if you need to tell HMRC about additional income.
• Speak to an accountant or tax adviser. If you're on a low income, the charity TaxAid gives free tax help.

Sources

• GOV.UK: Income Tax rates and allowances: current and past (Personal Allowance, income limit, bands for England, Northern Ireland and Wales)
• GOV.UK: Income Tax rates and Personal Allowances
• GOV.UK: Self-employed National Insurance rates (Class 4: 6% and 2%; Class 2)
• GOV.UK: Rates and allowances: National Insurance contributions (lower and upper profits limits)
• GOV.UK: Budget 2026 overview of tax legislation and rates, Annex A: rates and allowances (2027/28 figures)
• GOV.UK: Budget 2026 overview of tax legislation and rates, section 1.5 (trading allowance to £3,000 from 6 April 2027)
• GOV.UK: Tax-free allowances on property and trading income
• GOV.UK: Expenses if you're self-employed
• GOV.UK: Scottish Income Tax

More guides for UK online sellers

• Do You Pay Tax on Vinted? UK Rules & HMRC Limits 2026 – Own clothes vs reselling, the £1,000 allowance and the 30-sale reporting rule, in plain English.
• Vinted HMRC Form & NI Number Request: What to Do – Why Vinted is asking for your National Insurance number, the end-of-year deadline, and why it doesn't mean you owe tax.
• Vinted Tax Calculator UK: Free HMRC Limit Checker – Check your sales against the 30-sale / ~£1,700 reporting rule and the trading allowance, with a 2026/27 or 2027/28 tax-year switch. It checks limits, not your tax bill.
• eBay HMRC Reporting Threshold 2026: £1,707 or 30 Sales – What eBay counts towards £1,707, what it reports, and why a report isn't a tax bill.
• Got an HMRC Letter About Vinted or eBay Sales? What to Do – A calm step-by-step: check it's genuine, work out if you were trading, and reply on time.
• Free Vinted & eBay Profit Tracker Spreadsheet (UK) – A free download with tax-year tabs, profit per item and a check against the HMRC limits.
• Trading Allowance vs Expenses: Which Should Resellers Use? – The £1,000 allowance or your real costs? Why resellers who track stock costs often come out ahead with expenses.
• Do Resellers Need to Register for Self Assessment? – When reselling counts as trading, the £1,000 rule, and the 5 October and 31 January deadlines.
• Depop HMRC Reporting: Do You Pay Tax on Depop Sales? – What Depop reports, what it asks you for, and Depop's own example of being reported but owing no tax.
• Etsy UK Tax: HMRC Reporting Rules for Sellers 2026 – When Etsy reports you to HMRC, and why things you make to sell usually count as trading.
• Trading Allowance Rises to £3,000: What Budget 2026 Changed – The trading allowance is due to rise from £1,000 to £3,000 from 6 April 2027, subject to Finance Bill. When it starts, who it helps, and why £1,000 still applies until then.
• Why Is eBay Asking for My National Insurance Number? – Why eBay wants your NI number, what happens if you don't give it, and why giving it doesn't mean you owe tax.
• Selling Personal Items on eBay: Do You Pay Tax? (UK) – Clear-outs vs trading, the £6,000 Capital Gains Tax rule for valuable items, and why eBay may still report you.
• Facebook Marketplace & HMRC: Do They Report You? – What we could and couldn't confirm about Facebook Marketplace reporting, what Gumtree says, and why the tax rules are the same either way.
• Am I Trading? HMRC's Badges of Trade for Resellers – HMRC's nine badges of trade with Vinted and eBay examples, plus car boot sales: when selling becomes trading.
• Vinted Pro vs Personal Account: Does It Change Tax? – What Vinted says about Pro and standard accounts, what HMRC actually looks at, and why switching account type isn't what decides tax.
• Telling HMRC About Past Online Sales: Disclosure Guide – Realised you should have declared past reselling income? The routes GOV.UK describes, step by step, and how far back it goes.
• MTD for Resellers: Do eBay & Vinted Sellers Need It? – Most sellers won't need Making Tax Digital for Income Tax. The £50,000, £30,000 and £20,000 thresholds, and why they count sales, not profit.
• Whatnot UK Tax: Do Sellers Pay Tax and Does It Tell HMRC? – How Whatnot reports UK sellers to HMRC via Ireland, when live-selling income is taxable, Whatnot's fees as expenses, and the £90,000 VAT line.
• TikTok Shop UK Tax: When Sellers Pay and What HMRC Sees – TikTok Shop's 30 orders or €2,000 reporting rule, where to find your MRDP report, and why being reported isn't the same as owing tax.