With the cost of living continuing to rise across the UK, many people are looking for practical ways to reduce their tax bill and keep more of what they earn. From higher energy prices to rising food and fuel costs, every pound saved makes a difference.
The good news is that the UK tax system offers multiple legitimate ways to save money when filing your tax return online — whether you’re employed, self-employed, or earning additional income.
Below are 9 proven strategies to help you reduce your tax liability and file your UK tax return online more efficiently.
1. Check Your Tax Code Carefully
An incorrect tax code is one of the most common reasons people overpay tax in the UK. Your tax code determines how much Income Tax is deducted from your salary under PAYE.
How to check your tax code:
- Review your payslip, P60, or P45
- Log into your HMRC Personal Tax Account
- Contact HMRC directly if something looks wrong
Important:
An incorrect tax code can also lead to underpayment, which may result in an unexpected tax bill later. Always correct issues as early as possible.
2. Use Your ISA Allowance in Full
An Individual Savings Account (ISA) allows you to save or invest money tax-free, meaning you pay no tax on interest, dividends, or capital gains.
ISA options include:
- Cash ISA – tax-free savings interest
- Stocks & Shares ISA – tax-free investment growth
- Lifetime ISA (LISA) – ideal for first-time buyers or retirement (25% government bonus)
- Innovative Finance ISA – peer-to-peer lending investments
Key points:
- Annual ISA allowance: £20,000
- Allowance resets every 6 April
- Unused allowance cannot be carried forward
Using an ISA is one of the simplest long-term tax-saving strategies available in the UK.
3. Claim Pension Tax Relief
Pension contributions are one of the most powerful tax-saving tools available.
- Basic rate taxpayers (20%) get automatic tax relief
- Higher (40%) and additional rate (45%) taxpayers must claim extra relief via Self Assessment
Example:
A £100 pension contribution:
- Costs a basic rate taxpayer £80
- Costs a higher rate taxpayer £60 after claiming additional relief
Bonus tip:
Salary sacrifice pension schemes can reduce both Income Tax and National Insurance.
4. Check If HMRC Owes You a Tax Refund
Many people are due a tax refund without realising it. Common reasons include:
- Changing jobs
- Emergency tax
- Multiple income sources
- Overpaid Payments on Account (self-employed)
How to check:
- Log into your HMRC Personal Tax Account
- Look out for a P800 tax calculation
- Review previous Self Assessment submissions
Be cautious of scam emails or texts — HMRC never charges a fee to issue a refund.
5. Claim Marriage Allowance (If Eligible)
Marriage Allowance allows couples to transfer unused Personal Allowance, saving up to £252 per year.
You may qualify if:
- You’re married or in a civil partnership
- One partner earns under £12,570
- The other is a basic rate taxpayer
Claims can be backdated up to 4 tax years, making this a valuable overlooked relief.
6. Use the Starting Rate for Savings (Where Applicable)
If your income is low, you may qualify for up to £5,000 of tax-free savings interest under the Starting Rate for Savings.
Additionally, the Personal Savings Allowance (PSA) applies:
- Basic rate taxpayers: £1,000
- Higher rate taxpayers: £500
- Additional rate taxpayers: £0
ISAs remain tax-free regardless of income level.
7. Claim Allowable Expenses if You’re Self-Employed
If you’re self-employed, allowable expenses can significantly reduce your taxable profit.
Common deductible expenses:
- Office costs (internet, phone, stationery)
- Travel and mileage
- Equipment and software
- Professional fees (accountants, legal costs)
Expenses must be “wholly and exclusively” for business purposes.
Keep clear records and receipts — HMRC may request evidence.
8. Reduce Tax Through Workplace Benefits
Employees can also reduce taxable income through tax-efficient benefits, including:
- Salary sacrifice schemes
- Pension contributions
- Cycle to Work schemes
- Childcare support
- Bonus sacrifice
These benefits can lower both Income Tax and National Insurance, increasing take-home pay.
9. Don’t Miss Self Assessment Deadlines
Missing a deadline is one of the easiest ways to lose money.
Key dates:
- 31 October – paper tax returns
- 31 January – online tax returns and tax payment deadline
Late filing triggers an automatic £100 penalty, even if no tax is due.
Filing early helps avoid stress, errors, and unnecessary fines.
Bottom Line: Save More by Filing Your UK Tax Return Correctly
Saving money on your UK tax return isn’t about loopholes — it’s about knowing what reliefs and allowances you’re entitled to and claiming them correctly.
By following these 9 strategies, you can:
- Reduce your tax bill
- Avoid penalties
- Keep more of your income
For a smooth, stress-free experience, many taxpayers choose to file their UK tax return online with professional support.
FAQs
1. What is the UK Personal Allowance?
The Personal Allowance is £12,570 for the 2024/25 tax year and is frozen until April 2028.
2. How do I check my tax code?
You can check your tax code on your payslip, P60, or via your HMRC Personal Tax Account.
3. Are ISAs really tax-free?
Yes. ISAs are completely free from Income Tax and Capital Gains Tax.
4. Can I claim expenses if I’m self-employed?
Yes — as long as the expense is wholly and exclusively for business purposes.
