Income Tax and NI Combined Calculator
Income tax and National Insurance are calculated completely separately, using different bands and different rates, but they land on the same payslip and come out of the same salary — which is why seeing them combined, as one total deduction and one effective rate, is often more useful day to day than viewing either in isolation. This calculator shows both together, using your specific allowance, employment type and any additional income, rather than the standard assumptions a simpler calculator might default to.
Income Tax & National Insurance Calculator
See your full income tax and NI breakdown for 2026/27. Includes Scotland, pension and student loan.
Why Two Different Deductions Share One Payslip Line
Income tax funds general government spending and is calculated on total taxable income across the year. National Insurance is calculated separately, per pay period in practice, and historically funds specific benefits including the State Pension. They use different thresholds, different rates, and are administered under different rules — yet both are deducted automatically through PAYE and both reduce the same take-home figure. Seeing them combined, as this calculator does, answers the question most people actually have: not “how much income tax do I pay” or “how much National Insurance do I pay” separately, but “how much of my gross salary do I actually keep.”
This distinction matters more when comparing job offers or negotiating pay, since two roles with the same gross salary can produce a slightly different take-home figure depending on details like pension arrangements or employment type — seeing the full combined deduction, not just one piece of it, gives a more complete basis for that kind of comparison.
The Allowance Most People Don’t Know They Can Claim
Blind Person’s Allowance adds an extra £3,070 on top of the standard Personal Allowance for anyone registered as severely sight-impaired or blind, reducing taxable income by that additional amount before tax is calculated at all. This is a genuinely underclaimed allowance — it needs to be actively claimed with HMRC rather than being applied automatically, and can even be transferred to a spouse or civil partner if the person entitled to it does not use all of it themselves. If this applies to you or a family member, it is worth checking directly with HMRC that it has actually been applied, rather than assuming it has been picked up automatically.
Because it needs to be actively claimed rather than applied by default, it is genuinely possible to be eligible and simply not be receiving it — worth raising directly with HMRC if it has never been specifically discussed, rather than assuming that eligibility alone means it is already reflected in your tax code.
Employed and Self-Employed Pay National Insurance Differently
This is a genuinely important distinction this calculator handles explicitly: employees pay Class 1 National Insurance at 8% on earnings between the lower and upper thresholds, while self-employed individuals pay Class 4 at a lower 6% rate across the same band, both dropping to 2% above the upper threshold. This difference exists partly because self-employed people historically build up State Pension entitlement somewhat differently and do not receive certain employment-linked benefits that employee National Insurance contributions help fund. Selecting the correct employment type here genuinely changes the result, not just the label shown.
Same Income, Two Different NI Bills
On earnings of £45,000, an employee pays Class 1 National Insurance at 8% on the portion between £12,570 and £45,000, working out to roughly £2,594 for the year. A self-employed person on the identical £45,000 pays Class 4 at 6% on the same band instead, working out to roughly £1,946 — a difference of several hundred pounds purely from the employment type selected, on exactly the same income and exactly the same income tax calculation underneath.
When Your Tax Code Isn’t the Standard One
Most employees use the standard 1257L tax code, reflecting the standard £12,570 Personal Allowance, but plenty of tax codes are not standard — an adjustment for underpaid tax from a previous year, employment benefits taxed through your code, or additional allowances like the Blind Person’s Allowance can all shift your actual allowance above or below the default. This calculator lets you enter your own allowance figure directly rather than assuming everyone uses exactly £12,570, which matters for getting an accurate result if your own tax code differs from the standard one shown on a typical payslip. If you only need the income tax side without combining it with National Insurance, our Income Tax Calculator covers that in more depth, and our National Insurance Calculator does the same for NI specifically.
Frequently Asked Questions
How do I check what my actual tax code is?
Your tax code is shown on your payslip, your P60, or in your online Personal Tax Account with HMRC, and reflects your current allowance along with any adjustments currently being applied.
Does pension contribution reduce both income tax and National Insurance?
This depends on how the contribution is made — a salary sacrifice arrangement reduces both, since it lowers your gross pay before either is calculated, while a standard net pension contribution typically only affects income tax relief, not National Insurance.
Can I claim Blind Person’s Allowance if I am only partially sight-impaired?
Eligibility is based on being certified as severely sight-impaired or blind by a consultant ophthalmologist and registered with your local authority, not simply having some degree of vision impairment, so it is worth checking the specific registration criteria.
Why does my effective rate look lower than my highest tax band?
Your effective rate blends the 0% on your Personal Allowance with whatever higher rates apply to income above it, so it is always lower than your marginal (highest) rate unless your entire income falls within a single band.
Does this calculator handle multiple income sources?
Yes — the “other income” field lets you add income from a second source, combining it with your main salary for the tax calculation, though National Insurance treatment of multiple jobs can have additional nuances worth checking directly with HMRC.
Does Scotland use the same National Insurance rates as the rest of the UK?
Yes — National Insurance is not devolved and uses identical UK-wide rates and thresholds regardless of region. Only income tax bands differ for Scottish residents; National Insurance stays consistent everywhere.
Important Information
This calculator provides an estimate based on standard 2026/27 PAYE rates for general information purposes only and does not constitute tax advice. It does not account for every individual circumstance, such as benefits in kind or a more complex tax code adjustment. For advice specific to your situation, consult HMRC or a qualified accountant. See our Disclaimer for further information.