Turning a hobby into paid work is one of the most common ways women test a business idea. Whether you are selling handmade jewellery on Etsy, tutoring online, or delivering parcels at weekends, the moment money changes hands HMRC sees you as a potential trader. The good news is that the UK tax system gives most new earners a £1,000 trading allowance, so paperwork can wait until your income passes that point. This guide explains the 2026/27 thresholds, deadlines, and reliefs that matter when a passion project becomes profit. If you are ready to move beyond casual earning, see our guide to setting up a business today.
When Does a Side Hustle Become Taxable?
HMRC treats almost all income from side work as taxable from the first pound. That includes cash-in-hand jobs, digital sales, and referral commissions. Two reliefs keep very small earners out of Self Assessment. The first question most women ask about tax on a side hustle is whether their hobby counts as a business. The answer usually depends on whether you are trading with a view to profit, rather than occasionally selling personal items. If you are unsure whether to operate as a sole trader or a limited company, our comparison of sole trader and limited company structures can help.
The £1,000 Trading Allowance
The trading allowance is the simplest UK tax relief for micro-earners. It lets you earn up to £1,000 of gross trading income each tax year before you declare it to HMRC. You cannot use it alongside expenses on the same income. Instead, choose whichever saves more tax.
If your gross sales are £950 and your expenses are £400, the allowance wins because it reduces taxable profit to zero. If your gross sales are £2,000 and your expenses are £1,100, claiming actual expenses leaves £900 taxable. That is better than the £1,000 allowance, which would leave £1,000 taxable. The allowance applies to individuals, not households. Each person running a separate side business can claim their own £1,000.
Property and Asset Sales
Renting a spare room or driveway is covered by the £1,000 property allowance, separate from trading income. If you sell personal possessions or investments for a profit, Capital Gains Tax may apply. We expect the annual exempt amount for individuals in 2026/27 to remain at £3,000. You pay tax on gains above that at 10% or 20%, depending on your income band. Residential property attracts higher rates.
How Much Tax Will You Pay on a Side Hustle in 2026/27?
Once income exceeds the trading allowance, you pay Income Tax and usually National Insurance Contributions on profits. Profit is what remains after you deduct allowable expenses. Your exact tax liability depends on your total taxable income from all sources, including employment, pensions, and other self-employment.
Income Tax Thresholds
For 2026/27, we expect the personal allowance to remain at £12,570, based on current government freezes. You pay Income Tax only on total income above that figure. The basic rate of 20% applies to income between £12,571 and £50,270. The higher rate of 40% applies between £50,271 and £125,140. You pay 45% on income above £125,140. If your total income exceeds £100,000, your personal allowance reduces by £1 for every £2 above that threshold. Scottish taxpayers use different bands and rates set by the Scottish Government.
National Insurance for the Self-Employed
National Insurance is the next layer of tax on your side hustle. We expect Class 4 NICs of 6% in 2026/27 on self-employed profits between £12,570 and £50,270. You pay 2% on profits above £50,270. Class 2 NICs are a flat weekly payment, expected to be around £3.50 in 2026/27. From April 2024, Class 2 is no longer compulsory for self-employed people whose profits are above the small profits threshold, because Class 4 NICs now count towards contributory benefits. You may still choose to pay Class 2 voluntarily if your profits are below the threshold, because this protects your National Insurance record and entitlement to the State Pension and some benefits. You pay all NICs through Self Assessment.
VAT Registration Threshold
VAT is another milestone to watch for your side hustle. You must register if your taxable turnover from the side hustle exceeds £90,000 in any rolling twelve-month period. The threshold rose from £85,000 to £90,000 in April 2024. We expect it to stay at that level in 2026/27. Voluntary registration below the threshold can make sense if you sell to VAT-registered businesses. You can then reclaim input VAT.
Online Platforms and HMRC Data Sharing
Since January 2024, online marketplaces and gig platforms have had to report seller earnings to HMRC under international data-sharing rules. This means Etsy, eBay, Airbnb, Uber, Deliveroo, and similar platforms share your name, address, bank details, and total sales. HMRC can match this data against tax returns, so ignoring side income is risky. Platforms report your gross sales, not your profit. If your gross trading income is £1,000 or less, the trading allowance usually means you do not need to declare it. If your gross income is above £1,000, you must register for Self Assessment and report it, even if your actual profit after expenses is small.
Registering for Self Assessment and Key Deadlines
If your side hustle income is more than £1,000 in a tax year, you usually need to register for Self Assessment. The deadline is 5 October following the end of that tax year. The 2026/27 tax year runs from 6 April 2026 to 5 April 2027. The registration deadline for that income is 5 October 2027. The online tax return deadline is 31 January 2028, and any tax owed is due on the same date. If your bill is over £1,000 and less than 80% of your tax was collected through PAYE, you must also make payments on account, with the next instalment due by 31 July 2028. Missing the registration deadline can lead to penalties. Late filing penalties start at £100 even if no tax is due.
Reducing Your Side Hustle Tax Bill Legally
Understanding allowable expenses is central to tax planning for your side hustle. Claiming every allowable cost is the easiest way to cut your tax bill. Allowable costs must be incurred wholly and exclusively for the business. Common examples include stock, packaging, postage, website hosting, software subscriptions, phone and internet used for the business, and professional insurance. You can also claim accountancy fees and travel for business purposes. If you work from home, you can claim a flat-rate allowance based on the hours you work from home. Alternatively, you can apportion actual household bills. You cannot claim personal costs. These include clothing you could wear outside work or the daily commute to a regular workplace.
Keeping good records is a legal requirement. You must keep receipts, invoices, and bank statements for at least five years after the 31 January submission deadline. Digital bookkeeping apps can automate this and help you set money aside for tax. A simple rule of thumb is to reserve 20-30% of side hustle profit for Income Tax and National Insurance. Adjust this once you know your total annual income. Many women run side hustles alongside employment or caring responsibilities, so building this cash buffer early is particularly important.
Penalties and Common Mistakes
Common mistakes include treating gross sales as profit. You owe tax on profit after expenses, so record every cost. Another error is failing to declare income because it was paid in cash or through a personal account. HMRC receives information from online platforms and can use its powers to request bank records where it suspects undeclared income. A third trap is missing the 5 October registration deadline because you expect to earn under £1,000 but later exceed it. Register as soon as you realise you will pass the threshold to reduce penalties. Late filing penalties start at £100 and can rise to daily fines for prolonged delays. Interest also accrues on unpaid tax.
At Prowess, the women we speak to often say they wish they had treated the tax side seriously from the first sale, not the first £1,000. Get into the habit of recording income and costs from day one, registering on time, and setting aside money every month. That discipline turns a side hustle from a source of worry into a business you can grow with confidence.
