Tax Savings

How Side Hustle Businesses Can Reduce Tax Liabilities and Stay HMRC Compliant

Published: 01 May 2025
10 min read

Side hustles are on the rise in the UK, driven by the cost-of-living crisis, flexible working, and the desire for multiple income streams. Learn practical, HMRC-compliant ways to reduce your tax liability whilst keeping your business financially healthy.

Close up of businessman hand calculating budget checking bills, using calculator to calculate home finance budget management. Doing finance, budgeting and tax calculation, monthly expenses

But if you're earning extra money on the side—whether through freelancing, online selling, or offering services—you must manage your tax obligations correctly to avoid trouble with HMRC. Fortunately, there are HMRC-compliant ways to reduce your tax liability whilst keeping your business financially healthy.

In this guide, we explore practical tax-saving tips for side hustle businesses, based on HMRC rules and real-world accounting experience.

1

Choose the Right Business Structure

Your business structure impacts how much tax you pay. The two main options for side hustlers are:

Sole Trader

Simpler to run, lower admin, taxed at personal rates

Limited Company

More complex but tax-efficient if profits are high

Key insight: If your total income exceeds £50,000, trading through a limited company can reduce tax by allowing you to take a combination of salary and dividends.

Example:

A sole trader earning £60,000 may pay more in Income Tax and National Insurance than a limited company director drawing £12,570 salary and the rest as dividends.

Read our full guide on business structures
2

Open a Separate Business Bank Account

Using a dedicated bank account for your side hustle:

  • Makes it easier to track income and expenses
  • Simplifies your tax return and year-end accounts
  • Shows HMRC you are operating as a genuine business

Many providers offer free business banking for new small businesses.

3

Pay Business Expenses from the Business Account

It's essential to pay all business-related expenses directly from your business bank account—even if the amount is small. This helps maintain a clean audit trail and simplifies your bookkeeping and year-end accounts.

Avoid using your business account for personal spending, as this can complicate your records and raise unnecessary questions during an HMRC enquiry.

Best Practice:

If your business bank account doesn't have enough funds to cover a business expense, first transfer the required amount from your personal account to your business account. Then, make the payment from your business account. This keeps your records tidy and demonstrates professionalism to HMRC.

4

Claim Tax-Free Mobile Phone Use

If you're trading through a limited company, transfer your mobile contract into the business name.

HMRC allows one tax-free mobile phone per director, even if it's used for personal reasons—as long as the contract is in the company's name. This is a great way to save tax on a cost you're already incurring.

5

Internet and Broadband

If you're working from home:

  • You can claim a portion of your broadband costs as a business expense
  • Better yet, set up the broadband in the business name if possible
  • For sole traders, apportion a fair percentage (e.g. 50%) if the broadband is shared
6

Mileage and Vehicle Expenses

If you use your personal car for business:

Keep a Log

Track all business journeys (date, purpose, miles)

Claim Mileage

45p per mile (first 10,000 miles), then 25p

This is HMRC's approved rate and avoids the need to track fuel, insurance, and repairs separately.

7

Pay a Salary to Your Spouse or Partner

If your spouse or partner helps with your business (e.g. admin, delivery, marketing), and they're not using their personal tax allowance, consider paying them a salary.

This is allowed if:

  • The work is genuine
  • Payment is reasonable
  • You register for PAYE if needed

This can help use up their tax-free allowance and reduce your own taxable income.

8

Travel and Subsistence

If you travel for business purposes (not your normal commute), you can claim:

Public transport fares

Business mileage

Meals when travelling

According to HMRC, travel must be "wholly and exclusively" for business. Meals can be claimed if you're travelling for work and it's not part of your normal routine.

9

Use of Home as Office

If you work from home, you can claim a proportion of household costs, such as:

Rent or mortgage interest
Council tax
Gas, electricity, and water
Internet and phone

HMRC offers two options:

Flat Rate (Simpler Method)

£10 to £26/month depending on hours worked

Apportioned Actual Costs

More accurate, based on business use percentage

You'll need to keep records to justify your claim.

10

Contribute to a Pension

If your business is profitable and you don't need to withdraw all the funds, consider making pension contributions:

For Sole Traders

Claim as a deduction from total income

For Company Directors

Employer pension contributions are tax-deductible

This can reduce your corporation tax or income tax bill whilst saving for the future.

11

Keep Digital Records and Use Accounting Software

Using cloud-based tools like FreeAgent, QuickBooks, or Xero helps you:

Stay organised

Track income and expenses in real-time

Submit Making Tax Digital compliant VAT returns

HMRC is rolling out Making Tax Digital for Income Tax in future years. Being digital now avoids last-minute rushes.

12

Don't Forget Allowable Expenses

Examples of tax-deductible expenses:

Office supplies
Website costs
Software subscriptions
Marketing and advertising
Training related to your business
Professional memberships
Accountancy fees

Important: Always keep receipts and only claim items that are wholly and exclusively for business.

Final Thoughts

Running a side hustle is exciting and can provide real financial freedom. But as income grows, so do your tax responsibilities. With careful planning, and by using the tips above, you can reduce your tax bill legally and confidently whilst staying compliant with HMRC.

Need Help Setting Up or Managing Your Side Hustle Accounts?

Taxwise Accountancy, online accountants for side hustle businesses, offers expert advice, affordable accounting packages, and full digital support for side hustlers across the UK.