Side Hustle Tax Calculator UK 2026 — Self-Employment & Gig Economy

More people than ever have side hustles. Here’s how the tax works and what you need to do to stay on the right side of HMRC.

The Trading Allowance

Your Tax-Free Buffer

Rule	Detail
Trading Allowance	£1,000
What it covers	All self-employment income
No registration needed	If under £1,000
No expenses claimed	Can’t use both

How to Use It

Gross Income	Option 1: Trading Allowance	Option 2: Actual Expenses
£800	£0 tax (under allowance)	N/A
£1,500	Profit = £500 (£1,500 - £1,000)	Profit = £1,500 - expenses
£5,000	Profit = £4,000	Profit = £5,000 - expenses

Choose whichever gives lower taxable profit.

Example: Should I Use Trading Allowance?

Scenario	Gross Income	Actual Expenses	Trading Allowance Better?
Freelance writing	£3,000	£200	No (use expenses)
Selling crafts	£2,500	£1,800	No (use expenses)
Tutoring (no costs)	£4,000	£50	Yes (saves £950)
Deliveroo (fuel costs)	£6,000	£2,500	No (use expenses)

Tax Calculator

Understanding Your Tax Position

Your side hustle profit is added to your employment income, then taxed at your marginal rate.

Tax Rates 2026/27

Total Income	Tax Rate	NI Rate (Class 4)
£0-12,570	0%	0%
£12,571-50,270	20%	6%
£50,271-125,140	40%	2%
£125,140+	45%	2%

Side Hustle Tax Examples

Example 1: £30,000 Salary + £5,000 Side Hustle (£1,500 expenses)

Calculation	Amount
Employment income	£30,000
Side hustle gross	£5,000
Less expenses	-£1,500
Side hustle profit	£3,500
Total taxable income	£33,500
Already used Personal Allowance	In PAYE
Tax on side hustle (20%)	£700
Class 4 NI on profit (6%)	£210
Class 2 NI	£179
Total side hustle tax	£1,089
Side hustle net	£2,411

Example 2: £50,000 Salary + £10,000 Side Hustle (£2,000 expenses)

Calculation	Amount
Employment income	£50,000
Side hustle profit	£8,000
Amount at 20%	£270
Amount at 40%	£7,730
Tax (20% + 40% weighted)	£3,146
Class 4 NI (6%, then 2%)	£494
Class 2 NI	£179
Total side hustle tax	£3,819
Side hustle net	£4,181

Quick Calculation Table

Day Job Salary	Side Hustle Profit	Tax + NI	You Keep
£25,000	£2,000	£520	£1,480
£25,000	£5,000	£1,479	£3,521
£30,000	£2,000	£520	£1,480
£30,000	£5,000	£1,479	£3,521
£40,000	£5,000	£1,479	£3,521
£50,000	£5,000	£1,979	£3,021
£60,000	£5,000	£2,279	£2,721

Registration Requirements

When to Register

Situation	Action	Deadline
Income under £1,000	No registration needed	-
Income over £1,000	Register for Self Assessment	Oct 5 following tax year
First Self Assessment	File return	Jan 31 following tax year

How to Register

Step	Action
1	Go to gov.uk/register-for-self-assessment
2	Choose “self-employed”
3	Provide NI number and details
4	Receive UTR (Unique Taxpayer Reference)
5	Activate Government Gateway account

Timeline Example

Event	Date
Start side hustle	July 2025
Tax year ends	April 5, 2026
Register by	October 5, 2026
File return by	January 31, 2027
Pay tax by	January 31, 2027

Allowable Expenses

What You Can Claim

Expense	Example
Equipment	Laptop, tools, camera
Materials/stock	Products you sell
Travel	Business miles (45p/mile first 10k)
Phone/internet	Business proportion
Marketing	Website, advertising
Software	Subscriptions for business
Professional fees	Accountant
Insurance	Public liability
Home office	Simplified £6/week or proportional

What You Can’t Claim

Not Allowable	Why
Personal expenses	Not for business
Fines/penalties	Not deductible
Client entertaining	UK rule
Initial clothing	Unless uniform
Commuting	Travel to regular workplace

Simplified Expenses

Option	Amount
Working from home	£6/week flat rate
Vehicle	45p/mile (first 10,000), 25p after
Living in business premises	Based on occupants

Gig Economy Specifics

Platform-by-Platform

Platform	Are You Self-Employed?	Platform Reports to HMRC?
Deliveroo	Yes	Yes (from 2024)
Uber	Yes	Yes
Etsy	Yes	Possibly
eBay	Yes (if trading)	If over £1,000
Amazon FBA	Yes	Yes
TaskRabbit	Yes	Possibly
Airbnb	Yes (rental income)	Yes

HMRC Platform Data Sharing

From 2024, digital platforms must report sellers’ income to HMRC if earnings exceed £1,000 or you have 30+ transactions.

Platforms Reporting	What They Report
Marketplaces	Your sales, name, address
Rental platforms	Your rental income
Delivery apps	Your earnings

HMRC will know your side hustle income — don’t ignore tax obligations.

National Insurance

Classes of NI

Class	Who Pays	Rate
Class 2	Self-employed over £6,725 profit	£3.45/week (£179/year)
Class 4	Self-employed over £12,570 profit	6% (then 2% over £50,270)

NI Calculation Example

Profit	Class 2	Class 4	Total NI
£5,000	£0 (exempt)	£0	£0
£10,000	£179	£0	£179
£20,000	£179	£446	£625
£30,000	£179	£1,046	£1,225

Record Keeping

What to Keep

Record	How Long
Income records	5 years
Expense receipts	5 years
Bank statements	5 years
Invoices	5 years
Mileage log	5 years

Simple Tracking Methods

Method	Pros	Cons
Spreadsheet	Free, flexible	Manual work
Accounting app (FreeAgent, Xero)	Automated, reports	Monthly cost
Contractor apps (QuickBooks SE)	Mobile-friendly	Cost
Paper records	Simple	Hard to analyse

Common Side Hustles

Tax Treatment Summary

Side Hustle	Typical Expenses	Key Considerations
Freelance writing/design	Software, equipment	Home office
Tutoring	Materials, travel	Often few expenses
Delivery driving	Fuel, phone, bags	Mileage important
Selling crafts	Materials, postage	Stock costs
Renting spare room	Cleaning, utilities	£7,500 Rent-a-Room relief
Car rental (Turo)	Insurance, cleaning	Separate from driving
Social media	Equipment, software	Home office

Rent-a-Room Relief

If Renting Spare Room	Rule
First £7,500	Tax-free
Above £7,500	Taxed on profit
Separate from Trading Allowance	Can have both

Penalties for Non-Compliance

What Happens If You Don’t Register

Failure	Penalty
Late registration	£100 + interest
Late filing	£100 (immediate) + £10/day after 3 months
Late payment	Interest + surcharges
Deliberately wrong	Up to 100% of tax owed
Tax investigation	Stress, time, potential prosecution

Key Takeaways

1. £1,000 Trading Allowance — tax-free if under this
2. Register if over £1,000 — by October 5 after tax year
3. Keep records — 5 years minimum
4. Track expenses — can significantly reduce tax
5. HMRC sees platform data — they’ll know your income
6. Plan for tax — set aside 25-35% of profit

For related content, see our self-employment tax guide, dividend vs salary calculator, and take-home pay calculator.