UK Side Hustle Tax 2026: Complete HMRC & Threshold Guide

Whether you have already started earning from a side hustle or are about to, the same tax system applies to you: HMRC’s self-employment rules, the £1,000 trading allowance, Self Assessment registration, and — from January 2025 — platform reporting that means HMRC now receives earnings data from Etsy, Vinted, Deliveroo, Amazon, and dozens of other platforms automatically.

This guide covers the complete UK side hustle tax picture for 2026. It is structured as a reference guide you can return to as your income grows — starting with whether you need to do anything at all, moving through registration, filing, expenses, and National Insurance, and ending with the specific 2026 developments that affect side hustlers with growing income.

Do You Need to Do Anything About Tax Right Now?

Do You Need to Do Anything About Tax Right Now

The answer depends on one number: your total gross side hustle income in the tax year.

A tax year runs from 6 April to 5 April. The current tax year is 2026/27 (6 April 2026 to 5 April 2027). You are also responsible for the 2025/26 tax year if you earned from a hustle between 6 April 2025 and 5 April 2026.

If Your Gross Income is Below £1,000

You owe no tax on your side hustle income, are not required to register for Self Assessment, and do not need to tell HMRC anything. Keep records in case you are ever asked, but no action is needed.

If Your Gross Income is Above £1,000

You must register for Self Assessment by 5 October following the end of the tax year. For 2025/26 income: register by 5 October 2026. Filing and payment deadlines follow from registration.

Crossing £1,000 does not automatically mean you owe tax — it means you must register and report. Whether you owe any income tax depends on your total income from all sources compared to your personal allowance (£12,570 for 2025/26 and 2026/27).

The Gross Income Rule — the Most Important Detail

Gross income means the total amount paid to you by customers, clients, or platforms — before any deductions, expenses, or platform fees. It is not your profit. It is not what the platform paid you after taking its cut.

If buyers on Etsy paid you £1,200 and Etsy kept £180 in fees, your gross income for HMRC purposes is £1,200. If you did £800 of tutoring and £300 of dog walking, your combined gross income is £1,100. The threshold is measured on the combined total across all side hustle activities — not per activity.

The £1,000 Trading Allowance — the Foundation

Every UK individual has a £1,000 trading allowance per tax year. This allowance works as follows.

Below £1,000: Complete Exemption

If gross trading income stays below £1,000, the allowance exempts you entirely — no tax, no National Insurance, no registration, no reporting.

Above £1,000: Two Calculation Options

Once you are registered and filing, you choose between two methods for calculating your taxable profit:

OPTION A — TRADING ALLOWANCE: Claim a flat £1,000 deduction from your gross income. No receipts required. Taxable profit = gross income − £1,000.

OPTION B — ACTUAL EXPENSES: Claim your real, documented allowable expenses. Taxable profit = gross income − total allowable expenses.

You choose the method that produces the lower taxable profit. You cannot use both in the same year for the same activity.

When to Use Each Method?

Use Option A (trading allowance) when your actual expenses are less than £1,000. Freelancers, tutors, and most service-based side hustlers fall here — their costs are minimal and the flat allowance gives a larger deduction.

Use Option B (actual expenses) when your costs exceed £1,000. Delivery drivers, resellers with significant stock costs, and makers who buy materials should always calculate both and use the better result.

The decision is purely mathematical. Run both numbers. For the detailed explanation including worked examples, see our guide on how the £1,000 trading allowance works in full.

HMRC Platform Reporting — What They Already Know?

HMRC Platform Reporting — What They Already Know

Since January 2025, UK digital platforms are legally required to report seller and earner data to HMRC. This is one of the most significant changes to side hustle tax enforcement in a decade.

Which Platforms Report?

Any platform that facilitates the sale of goods, the provision of services, rental of transport or property, or online delivery services — if they operate in the UK or have UK users — must report. This includes Etsy, Vinted, eBay, Amazon Marketplace, Airbnb, Deliveroo, Uber Eats, Just Eat, Amazon Flex, TaskRabbit, and dozens more.

What Triggers a Report?

A platform must report a specific seller or earner to HMRC if, in the calendar year, they meet either of these thresholds:

30 or more transactions on the platform, or
Approximately £1,700 in total sales (€2,000 at the applicable exchange rate)

Either threshold — not both — triggers the report. Crossing 30 transactions is enough even if total sales are below £1,700.

What HMRC Receives?

Your name, home address, National Insurance number, and gross sales figure for the calendar year.

What HMRC Does With It?

HMRC cross-references the platform report against your Self Assessment records. If you have filed a return and declared the income, no action follows. If you have not filed and you crossed the platform reporting threshold, you may receive a nudge letter prompting you to check whether you need to register.

The Critical Point

This system means HMRC now has data on a large proportion of UK side hustlers. The calculation of whether to declare is no longer “will they find out?” — the answer is frequently yes. The practical question is whether you have declared correctly and on time.

If you have received a nudge letter: register for Self Assessment as soon as possible, gather your income records, and file. Responding promptly and voluntarily is treated significantly more favourably than ignoring the letter.

For the full breakdown of what this crackdown means in practice, see our guide on what HMRC’s platform reporting crackdown actually means.

Registering for Self Assessment

Registration is required when gross income from any self-employed activity exceeds £1,000 in the tax year.

The Deadline: 5 October

You must register by 5 October following the end of the tax year in which you first crossed the threshold. For 2025/26 income, register by 5 October 2026. For 2026/27 income, register by 5 October 2027.

How to Register?

Go to gov.uk/register-for-self-assessment. Select self-employed or sole trader. You will need your National Insurance number, an email address, and identity verification documents. HMRC posts your Unique Taxpayer Reference (UTR) to your registered address within 10–14 working days.

Allow 20–25 working days from registration to having a fully active account — two separate letters arrive (your UTR, then a Government Gateway activation code). Both are needed before you can file.

Already Registered From a Previous Period?

If you have a UTR from previous self-employment, use form CWF1 to notify HMRC of new self-employment rather than re-registering from scratch.

For the complete step-by-step registration guide including the identity verification process and what to do if you have missed the deadline, see our guide on whether you need to register as self-employed.

Filing Your Self Assessment Return

Once registered, you file a Self Assessment return covering each tax year (6 April to 5 April).

The Filing Deadline: 31 January

The online Self Assessment deadline for the 2025/26 tax year (ended 5 April 2026) is 31 January 2027. Paper returns have an earlier deadline of 31 October 2026.

File early. There is no benefit to waiting until January and significant cost to missing the deadline (automatic £100 penalty on day one, escalating further).

What Goes on the Return?

Your self-employment income is reported on the SA103 pages (short form for simpler cases, full form for more complex ones). You report:

Total gross turnover (everything customers paid you)
Either the trading allowance (Option A) or itemised allowable expenses (Option B)
Net profit (calculated automatically by the return)
This is added to any other income (salary, savings interest, rental income)
Minus your personal allowance (£12,570)
Equals taxable income — which determines the tax owed

For the complete step-by-step filing guide covering the Government Gateway process, SA103 pages, and how to request that HMRC does not collect underpayments via your tax code, see our guide on how to declare side hustle income to HMRC.

The Tax Calculation — Exactly What You Owe?

The Personal Allowance

Everyone in the UK has a personal allowance of £12,570 for 2025/26 and 2026/27. Income below this amount is tax-free.

Income Tax Rates for 2026/27

0%: income up to £12,570 (personal allowance)
20% basic rate: income between £12,571 and £50,270
40% higher rate: income between £50,271 and £125,140
45% additional rate: income above £125,140

How Side Hustle Income Stacks on Top of Employment Income?

Your salary and your side hustle income are assessed together. If your salary is £30,000 and your side hustle generates £3,000 in profit, your total income is £33,000. Your personal allowance (£12,570) is already fully used by your salary. Every pound of side hustle profit above the £1,000 trading allowance is taxed at 20%.

Taxable side hustle profit: £3,000 − £1,000 = £2,000

Income tax at 20%: £400

For someone with no other income and a total income well below £12,570, side hustle profit may attract no income tax at all — even above the £1,000 threshold. But registration and filing are still required.

Higher and Additional Rate Taxpayers

If your employment income already puts you in the 40% band, every pound of side hustle profit above the trading allowance is taxed at 40%. A £3,000 side hustle profit costs £800 in income tax at 40% — double the basic rate figure. Plan for this.

National Insurance for Side Hustlers

Class 2 National Insurance — Abolished for Most From April 2024

Compulsory Class 2 National Insurance — the flat weekly charge for self-employed people — was abolished from April 2024 for the majority of sole traders. Most side hustlers no longer pay a separate Class 2 charge.

Voluntary Class 2 NICs (£3.45/week for 2026/27) remain available for those with profits below the small profits threshold (£6,845 for 2026/27). Paying voluntarily counts toward qualifying years for the State Pension and the contributory period for new-style ESA. For anyone building pension entitlement, this is worth considering.

Class 4 National Insurance

Class 4 NICs apply on self-employed profits above the annual lower profits limit. For 2026/27:

6% on profits between £12,570 and £50,270
2% on profits above £50,270

This means Class 4 NICs only bite when your side hustle profit exceeds £12,570. For most side hustlers, this is unlikely unless the hustle has scaled significantly.

For employed side hustlers: your salary already takes you above the £12,570 threshold in most cases. Every pound of side hustle profit is therefore subject to Class 4 NICs at 6% from the first pound. Add income tax (20%) and Class 4 NICs (6%) and the effective tax rate on side hustle profit for a basic-rate employed person is 26%.

For the full explanation of Class 2 vs Class 4 and how they interact with employment income, see our guide on the difference between Class 2 and Class 4 NICs.

Allowable Expenses — What You Can Deduct

If you use Option B (actual expenses) instead of the trading allowance, you can deduct the following types of costs from your gross income. All claims must be wholly, exclusively, and necessarily for the purposes of the trade.

Costs of Goods and Materials

Stock purchased for resale. Raw materials used in making products. Packaging supplies.

Platform and Transaction Fees

Etsy listing fees, transaction fees, and payment processing fees. eBay final value fees. PayPal transaction fees. Amazon Marketplace fees. Any fees deducted by platforms before paying you out.

Equipment and Tools

Computers, phones, cameras, and tools used for the business — claimed as a capital allowance or under Annual Investment Allowance. If the item is used partly personally, only the business-use proportion is deductible.

Travel and Mileage

Business mileage using HMRC’s simplified rates: 45p per mile for the first 10,000 business miles per tax year (25p/mile thereafter), for cars and vans. 20p/mile for bicycles. Mopeds: 24p/mile. Keep a mileage log — date, from, to, purpose, distance.

Note: the journey from home to a regular fixed workplace is not a deductible business journey. Travel between business locations, to client meetings, or to collect stock is deductible.

Insurance

Business insurance, public liability insurance, and hire-and-reward insurance for delivery work are deductible.

Marketing and Advertising

Website costs, social media advertising spend, Etsy wardrobe boosts, and any paid promotion of your business.

Professional Fees

Accountant fees and software subscription costs (accounting software, invoicing tools) are deductible.

Training

Costs of training directly related to your existing business — refreshing or improving skills you already use. Training to move into a completely new trade is not deductible.

What You Cannot Claim?

Personal and domestic costs. The cost of clothing worn for work (unless it is a uniform or protective clothing). Food and drink (except specific conditions for long-distance travel). Fines and penalties. Costs that have both personal and business use where the business element cannot be clearly separated.

For the full list of every expense you can claim, see our guide on every side hustle expense you can claim in the UK.

Payment on Account — the Trap That Catches First-year Filers

Payment on Account — the Trap That Catches First-year Filers (2)

This section catches more first-time Self Assessment filers off guard than any other aspect of the system.

What is Payment on Account?

If your Self Assessment tax bill exceeds £1,000 and less than 80% of your total income was taxed at source (PAYE), HMRC requires advance payments toward the following year’s tax bill.

What This Means in Practice?

At your first January deadline, instead of paying only the current year’s tax, you pay:

The current year’s tax (balancing payment)
PLUS 50% of the current year’s tax as a first payment on account for next year

Then, the following July, you pay another 50%.

Worked Example

Your 2025/26 side hustle tax bill is £1,400 (income tax + Class 4 NICs combined).

By 31 January 2027 you pay:

£1,400 (2025/26 balancing payment)
£700 (50% payment on account for 2026/27)
Total: £2,100 in January

Then by 31 July 2027:

£700 (second payment on account for 2026/27)

That is £2,800 paid in your first tax year — not the £1,400 many people expect.

How to Prepare?

Set aside 25–30% of every side hustle payment into a separate savings account from day one. Treat it as money already earmarked for HMRC. The January shock is exclusively a cash-flow problem that consistent saving eliminates.

Making Tax Digital — What Changes From 2026?

Making Tax Digital for Income Tax (MTD ITSA) is HMRC’s shift toward digital tax reporting. It began rolling out from April 2026.

Who is Affected Now (April 2026)?

Sole traders and landlords with combined gross business and property income above £50,000 per year must use MTD-compatible software, keep digital records, and submit quarterly updates to HMRC. An annual final declaration replaces the traditional annual return.

Who is Affected From April 2027?

The threshold drops to £30,000 for the 2027/28 tax year.

Who is Not Yet Affected?

Anyone earning below £50,000 from self-employment and property combined continues to use the traditional annual Self Assessment return. The vast majority of side hustlers are not affected by MTD at current thresholds.

What Changes for Those Above the Threshold?

Instead of a single January deadline, you submit quarterly digital updates (by 7 August, 7 November, 7 February, and 7 May), plus a final declaration by 31 January. The tax due is still paid by 31 January. MTD-compatible software is required — free and paid options exist including HMRC’s own free MTD service for simpler cases.

The Most Important Deadlines

All deadlines below are for the 2025/26 and 2026/27 tax years.

Register for Self Assessment

2025/26 income: by 5 October 2026
2026/27 income: by 5 October 2027

File Your Return (Online)

2025/26 return: by 31 January 2027
2026/27 return: by 31 January 2028

Pay Tax Owed

2025/26: by 31 January 2027
First payment on account (2026/27): by 31 January 2027
Second payment on account (2026/27): by 31 July 2027

Penalties for Late Filing

Day 1 late: automatic £100
3 months late: £10/day (up to 90 days = up to £900)
6 months late: 5% of tax owed or £300 (whichever is higher)
12 months late: further 5% of tax owed or £300

Penalties for Late Payment

Interest accrues daily at HMRC’s current rate (7.25% per year as of June 2026 — this changes periodically)
30 days late: 5% surcharge on tax owed
6 months late: further 5%
12 months late: further 5%

For the exact late-filing and late-payment penalty rates and what to do if you have already missed a deadline, see our guide on the exact late-filing and late-payment penalties.

Worked Examples

Example 1: Employed Teacher, £1,800 Tutoring Income

Salary: £34,000. Personal allowance already fully used.

Gross tutoring income: £1,800.

Option A (trading allowance): taxable profit = £800.

Income tax at 20%: £160.

Class 4 NICs at 6% (salary already above £12,570): £48.

Total tax: £208.

Net from tutoring after tax: £1,592.

Registration required (gross income > £1,000). File by 31 January 2027. If total tax bill exceeds £1,000, payments on account also due.

Example 2: No Other Income, Dog Walking Only

Gross dog walking income: £4,800.

Option A (trading allowance): taxable profit = £3,800.

Total income: £3,800 — below £12,570 personal allowance.

Income tax: £0.

Class 4 NICs (profit below £12,570): £0.

Total tax: £0.

Must still register (gross income > £1,000) and file a return. Tax bill is zero but the filing obligation exists.

Example 3: Amazon Flex Driver With High Costs

Gross Amazon Flex income: £8,500.

Actual expenses (fuel £2,200 + insurance £1,800 + maintenance £400): £4,400.

Option A (trading allowance): taxable profit = £7,500.

Option B (actual expenses): taxable profit = £4,100.

Decision: use Option B.

Employment salary: £28,000 (personal allowance already used).

Side hustle taxable profit: £4,100.

Income tax at 20%: £820.

Class 4 NICs at 6%: £246.

Total tax: £1,066.

Tax bill exceeds £1,000. Payments on account apply. By 31 January 2027, driver pays £1,066 + £533 (first POA) = £1,599. Second POA of £533 due 31 July 2027.

Example 4: Vinted Reseller Crossing the Threshold Mid-year

Gross Vinted income: £1,050. Stock costs: £320. Postage and packaging: £180. Total actual expenses: £500.

Option A (trading allowance): taxable profit = £50.

Option B (actual expenses): taxable profit = £550.

Decision: Option A gives lower taxable profit (£50).

With employment income of £22,000 (personal allowance used):

Income tax on £50 at 20%: £10.

Class 4 NICs on £50 at 6%: £3.

Total tax: £13.

Registration still required (gross income > £1,000). Tax is minimal but must be filed

Frequently Asked Questions

Does HMRC know about my side hustle before I register?

Potentially yes, if you have crossed a platform’s reporting threshold (30 transactions or approximately £1,700 in annual sales). Platforms including Etsy, Vinted, eBay, Deliveroo, Amazon, and Airbnb have been reporting UK earner data to HMRC since January 2025. If you received a nudge letter from HMRC, register and declare as soon as possible.

Can I earn from more than one side hustle and keep the allowance?

The £1,000 trading allowance is per person, not per activity. Your combined gross income from all side hustles is measured against the single £1,000 allowance. Earn £600 from Vinted and £500 from tutoring — combined gross income is £1,100, above the threshold, registration required.

Does my side hustle affect my personal allowance?

Your personal allowance (£12,570) applies to your total income from all sources. A side hustle adds to your total income. If your salary already uses all your personal allowance, side hustle profit is fully taxable from the first pound above the trading allowance. Your personal allowance does not reset for the side hustle.

What is the difference between registering for Self Assessment and registering as self-employed?

For a sole trader, they are the same process. Registering for Self Assessment as a self-employed person registers you for both simultaneously. You do not need a separate business registration unless you want to trade under a business name at Companies House.

Can I claim the trading allowance even if my actual expenses are higher?

No. You choose one method. If your actual expenses exceed £1,000, you should use the actual expenses method (Option B) as it gives a lower taxable profit. The trading allowance (Option A) is only beneficial when actual expenses are less than £1,000.