๐Ÿ‡ฌ๐Ÿ‡ง 2026/27 ยท Free guide ยท No sign-up

Am I paying too much tax?

Millions of UK workers overpay income tax every year โ€” and most never know. Here are the 8 most common causes, and exactly what to do about each one.

Check your tax code โ†’How to claim a refund

1 in 3

UK employees is thought to be on the wrong tax code at some point

ยฃ350

Average annual overpayment for someone on the wrong code

4 years

How far back you can claim a tax refund from HMRC

8 reasons you might be overpaying

The most common causes of overpaid tax.

01

Wrong tax code

The most common reason. If your employer or HMRC has assigned you the wrong tax code, you could be paying tax on money you're entitled to keep. The standard code is 1257L for most people. Codes like BR, 0T, or D0 applied to your main job are almost always wrong.

Common & impactful
02

Emergency tax code

When you start a new job without a P45, or HMRC can't verify your details, HMRC puts you on an emergency code (1257L M1 or 0T M1). This often means you pay too much tax until your code is corrected. HMRC corrects this automatically, but it can take months.

Common & impactful
03

Two jobs with wrong code allocation

If you have two jobs, only one job should have your personal allowance applied to it. If both jobs use a standard code with a personal allowance, you'll under-pay โ€” but if neither does (both on BR), you'll overpay. HMRC should split it automatically, but errors are common.

Worth checking
04

Stopped working mid-year

If you left employment partway through the tax year, you paid tax as if you'd earn that salary for the full year. Since you didn't, you're owed a refund of the 'unused' personal allowance for the remaining months. This doesn't happen automatically โ€” you need to claim.

Worth checking
05

High income child benefit charge not accounted for

If you or your partner earn over ยฃ60,000 and receive Child Benefit, you may owe a High Income Child Benefit Charge via self-assessment. Conversely, if you claimed Child Benefit and shouldn't have paid full benefit, adjustments may be owed.

Often missed
06

Pension contributions not claimed via self-assessment

If you contribute to a pension via 'relief at source' and are a higher-rate taxpayer, your provider only claims 20% basic-rate relief on your behalf. You must claim the additional 20% (or 25% in Scotland) yourself via self-assessment. Many people miss this.

Worth checking
07

Marriage Allowance not claimed

If you're married or in a civil partnership and one of you earns below ยฃ12,570, the lower earner can transfer ยฃ1,260 of their personal allowance to the higher earner โ€” saving up to ยฃ252/year in tax. Many couples don't know about this.

Often missed
08

Expenses not claimed (self-employed / PAYE)

Employed people can claim tax relief on job-related expenses not reimbursed by their employer โ€” professional subscriptions, uniforms, mileage above 45p/mile. The average unclaimed relief is ยฃ120/year. You can backdate 4 years.

Often missed

Step 1: Check your tax code.

Your tax code is printed on your payslip, your P60, and in your HMRC personal tax account. The most common correct code is 1257L โ€” this gives you the standard ยฃ12,570 Personal Allowance. Any deviation from this is worth investigating.

1257L โœ“Standard โ€” full personal allowance
BR โš Basic Rate only โ€” no allowance (second job code)
0T โš No personal allowance โ€” often emergency or new job
D0 โš All earnings taxed at 40% โ€” should only be on second job
W1/M1 โš Non-cumulative โ€” emergency basis, often temporary
Use our tax code checker โ†’

Step 2: How to claim your tax refund.

If you've overpaid tax, there are three ways to get it back:

1

Through self-assessment

If you complete a self-assessment tax return, any overpaid tax will be shown on your return and refunded automatically (usually within 5 weeks of filing).

2

Via your HMRC Personal Tax Account

Log in at gov.uk/personal-tax-account. Under 'Check your Income Tax', you can see if you've overpaid and request a refund directly. This covers the current and previous tax year.

3

Using a specialist tax refund service

Services like RIFT and TaxBack check up to 4 years of payslips for free and handle the HMRC claim process for you. They take a commission (typically 28โ€“35%) from any refund โ€” but you pay nothing if there's no refund to collect.

Think you've been overpaying tax?

RIFT Tax Refunds check your last 4 years of payslips for free. No refund, no fee. Average claim is ยฃ1,650.

Get a free refund check with RIFT โ†’Read the full guide

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