UK PAYE and tax code specialists

Is HMRC charging you the right amount of tax?

Nearly one in three UK taxpayers are on the wrong tax code. TaxChecker lets you check your own PAYE position in minutes, catch any overpayments, and see exactly what to claim back. Fully private. Nothing shared with HMRC, nothing shown to anyone but you.

Free for the first 50 sign-ups Results in under 3 minutes UK tax year 2026/27

Why professionals trust TaxChecker

Bank-grade encryption UK GDPR compliant Results in under 3 minutes Nothing shared with HMRC

What we check

Every corner of your PAYE position, reviewed in one place

Our engine mirrors HMRC's own calculations, then compares them against your payslip, tax code, and employment history to surface anything that looks off.

Tax Code Check

Decode every letter and number in your tax code. We flag outdated codes, emergency codes, and deductions you may not know you are paying.

PAYE Calculator

See exactly how HMRC arrives at your take-home pay, with a breakdown of income tax, National Insurance, and pension contributions.

P800 Refund Check

Find out whether HMRC owes you money from previous tax years. We mirror the P800 end-of-year calculation so you know exactly what to claim.

Payslip Analysis

Drop in a payslip and the calculator pulls out the numbers, verifies each deduction, and explains anything that looks unusual in plain English. The file stays in your session and is discarded on exit.

Take-Home Forecasting

Model a pay rise, a new job, or a pension change before you commit. See the impact on your net pay to the nearest pound.

HMRC Change Monitor

We track HMRC rate changes, allowance updates, and code notices so you hear about anything that affects your pay before your employer does.

How it works

Three steps, fully private, no one else sees your numbers

No account, no data sharing, no HMRC notification. What you enter is for your eyes only.

01

Enter only what you want to check

Type in your tax code, salary, and pension figures. They stay inside your session. We never send anything to HMRC, we never share data with third parties, and nothing is kept once you close the page unless you explicitly ask us to save a profile.

02

The numbers are crunched privately

Our calculator mirrors HMRC's own PAYE and tax code logic, then runs against the figures you entered. No one reviews the results. Not our team, not HMRC, not anyone else. There is no human in the loop.

03

Only you see the result

You get a clear, private breakdown of what you owe, what you may be owed, and exactly what to do next. If you want to claim a refund, we draft a ready-to-send letter for you to submit to HMRC yourself. We never contact HMRC on your behalf.

About TaxChecker

Built by people who have fought HMRC on their own tax code, and won.

TaxChecker exists because the UK tax system is unnecessarily opaque. Most people cannot tell from their payslip whether they are paying the right amount, let alone reclaim what they are owed.

We built a calculator that mirrors HMRC's own numbers, pulls the detail from your payslip inside your own session, and explains every deduction in plain English. No account. No data sharing. No HMRC notification. To mark the launch, the first 50 sign-ups get full access at no cost, for life.

1 in 3
UK taxpayers are on the wrong tax code at some point
£689
Average P800 tax refund reported by HMRC
3 min
Average time to complete a full TaxChecker review
50
Launch places available, free for life

Frequently asked

Straight answers to the questions we hear most

Is TaxChecker affiliated with HMRC?
No. TaxChecker is an independent service and is not affiliated with HMRC, His Majesty's Revenue and Customs, or GOV.UK. We mirror HMRC's published calculation rules to help you verify your own position, but any changes to your tax account must be made with HMRC directly.
How much does TaxChecker cost?
TaxChecker is a paid service once we go live. To mark the launch, the first 50 sign-ups receive full access at no cost, for life. After the first 50 places are taken, pricing is published on the sign-up page. There are no hidden fees, no ads, and we never take a percentage of your refund.
How secure is my information?
All data is sent over HTTPS using modern encryption. By default, we do not store your personal details once a calculation is complete. If you choose to save a profile, data is encrypted at rest and held in UK-based infrastructure under UK GDPR.
Can TaxChecker file a refund on my behalf?
Not directly. We are not a tax agent. We show you exactly what to claim, generate a letter or HMRC-ready summary, and guide you through the free GOV.UK process. You keep 100% of any refund rather than paying a rebate firm a cut.
Which tax year does TaxChecker support?
TaxChecker is updated for the current UK tax year, including all published HMRC rate changes, allowance updates, and code notices. Historic checks are supported back to the 2020/21 tax year.
Do you provide regulated tax advice?
No. TaxChecker is an informational tool. It does not constitute regulated financial or tax advice under the UK Financial Services and Markets Act. If your situation is complex, we recommend speaking to a chartered tax adviser.

Contact

Get in touch

Questions, feedback, or a tax situation that does not fit the calculator? Send us a message and we will reply within one working day.

Hours
Monday to Friday, 09:00 to 17:30 UK time
Based in
United Kingdom