HMRC Tax Calculator UK 2026/27: Which One You Need

There is no single HMRC tax calculator. There are at least seven, each built for a single slice of the tax code, scattered across gov.uk under different URLs and owned by different teams. The one most people reach for first is the income tax estimator, which handles a simple PAYE salary and stops dead the moment your life is more complicated than one salary and one tax code.

This is the editorial guide HMRC will never write. Which of the seven tools to reach for in which situation, what each one quietly leaves out, and where the official output is correct but misleading. The 2026/27 numbers throughout. General information about how UK tax works, not personal tax advice - if your situation is unusual, pay an accountant.

Contents

• The seven HMRC tax calculators and what each does
• What HMRC's calculators deliberately skip
• UK tax bands and thresholds for 2026/27
• Worked example: £35,000 PAYE
• Worked example: £75,000 PAYE plus £8,000 dividends
• Worked example: £110,000 and the 60% trap
• Worked example: £45,000 self-employed sole trader
• When HMRC's calculator is the right tool
• Frequently Asked Questions

The seven HMRC tax calculators and what each does

HMRC's calculators are scattered across gov.uk under different URLs, owned by different teams, and indexed inconsistently. The closest thing to a master page is HMRC tools and calculators on gov.uk, which lists them alphabetically but does not tell you which to use when. Here is the actual map.

That is seven distinct tools, each with its own quirks. There is also an obscure eighth - the National Insurance contributions calculator for the self-employed, buried in the Class 2/4 guidance pages - which most people end up reaching via the self-assessment estimator anyway.

None of these tools talks to any of the others. Run the income tax estimator on a £90,000 salary and it will not warn you that an £8,000 dividend on top would push part of your income into the 60% trap. Run the SDLT calculator and it has no view of your income at all. The picture HMRC presents is compartmentalised by design - and that compartmentalisation is where most of the optimisation room a proper take-home pay tool surfaces actually lives.

What HMRC's calculators deliberately skip

This is where the gap between "what gov.uk shows you" and "what you can legally pay" starts to matter.

Salary sacrifice is not modelled anywhere. The most powerful single tax-reduction lever available to a UK PAYE worker is sacrificing salary into a pension via a salary-sacrifice arrangement. Done properly, it cuts income tax, employee National Insurance, and (where the employer passes it back) employer National Insurance too. HMRC's income tax estimator has no field for it. Type your gross salary and your tax code, and the calculator gives you the number you would owe if you took the whole salary as cash. The fact that you could legally route £10,000 into your pension and pay zero income tax and zero NI on that slice is something the tool refuses to engage with.

The £100k personal allowance taper interaction with pension contributions is missing. Cross £100,000 and your personal allowance starts vanishing at £1 lost for every £2 of income above the threshold. A pension contribution made via salary sacrifice (or grossed up through relief at source) reduces your "adjusted net income" for taper purposes, which means a well-sized contribution can claw the personal allowance back and turn the effective relief on that contribution into 60% or higher. HMRC's calculator never even tells you the taper exists. You have to know it is there.

Student loan plan 5 is missing from some tools. Plan 5 started in August 2023 for English and Welsh students who began undergraduate study from that academic year. The threshold is £25,000 and the term is 40 years before write-off. HMRC's older income tax estimator has been slow to incorporate it, and the self-assessment tool only handles it correctly if you tick the right boxes in the right order. Anyone on plan 2 (most current graduates) and plan 5 simultaneously - which is rare but possible - gets nothing from the official tool.

Combined dividend-plus-PAYE is split across two tools. A director-shareholder paying themselves a small salary plus dividends has to model the salary in the income tax estimator and the dividend tax in the self-assessment tool, then reconcile by hand. The dividend allowance of £500 sits inside the basic-rate band, gets used up before the higher-rate dividend rate kicks in, and interacts with the personal allowance in ways the standalone dividend page does not show.

Scottish bands are only on some tools. The income tax estimator handles Scottish rates. The marriage allowance calculator does not always make it obvious. The dividend tax page applies the UK-wide dividend rates regardless of where the taxpayer lives, which is correct (dividend tax is not devolved) but routinely confuses Scottish higher earners.

Childcare loss at £100k is not modelled. Cross £100,000 of adjusted net income and you lose tax-free childcare and the 30 hours of free childcare in England. For a parent of two pre-school children that is worth another £4,000-£5,000 a year on top of the personal allowance taper, pushing the effective marginal cost of crossing the line toward 80%. HMRC's tools do not gesture at this at all.

HMRC's calculators are correct on the slice they cover but conservative on everything else. They do not advise. They model the tax owed assuming you do nothing to optimise, then stop. That is HMRC behaving as a tax authority, not as a planner. And it costs people money.

UK tax bands and thresholds for 2026/27

The numbers you need to keep straight for the worked examples below.

Income tax (England, Wales, Northern Ireland), 2026/27:

National Insurance (employee Class 1), 2026/27:

• £0 - £12,570: 0%
• £12,571 - £50,270: 8%
• £50,271+: 2%

National Insurance (self-employed Class 4), 2026/27:

• £0 - £12,570: 0%
• £12,571 - £50,270: 6%
• £50,271+: 2%

Class 2 NI was abolished for most self-employed people from April 2024; voluntary Class 2 contributions remain available for those topping up the State Pension record.

Other 2026/27 allowances and rates:

• Personal Savings Allowance: £1,000 (basic rate), £500 (higher rate), £0 (additional rate)
• Dividend allowance: £500
• Dividend tax: 10.75% (basic), 35.75% (higher), 39.35% (additional) - basic and higher rates rose by 2 percentage points for 2026/27
• Capital Gains Tax (from October 2024): 18% / 24% on residential property, 18% / 24% on other gains
• CGT annual exempt amount: £3,000
• ISA allowance: £20,000
• LISA allowance: £4,000
• Pension annual allowance: £60,000
• State Pension (full new State Pension): £241.30 per week

Bands and allowances have been frozen since 2021. CPI has been roughly 25% over the same window, so the real-terms personal allowance has quietly shrunk by about a quarter. The Treasury collects roughly £40 billion a year extra from the freeze, which is the largest stealth tax rise in recent memory. The UK tax brackets 2026/27 explainer has the full background on how the freeze compounds year-on-year.

Worked example: £35,000 PAYE

The simplest case. A standard PAYE worker on a single salary with tax code 1257L.

HMRC's income tax estimator returns:

• Personal allowance: £12,570 at 0%
• Basic rate: £22,430 at 20% = £4,486
• Total income tax: £4,486
• Employee NI: £1,794 (8% of £22,430)
• Take-home: £28,720 per year, or £2,393 per month

For this case, the HMRC tool is right. A reader on £35,000 with no pension salary sacrifice, no student loan, and no other income gets a number from gov.uk they can rely on.

What HMRC will not tell them: a 5% personal pension contribution via salary sacrifice (£1,750 a year) would cost roughly £1,330 in take-home and add £1,750 to the pension pot, with the employer also saving 15% employer NI on the sacrificed slice that a good employer passes back. The official tool is silent on this entirely. Our take-home pay calculator has the sacrifice field built in. The P60 explainer covers how to cross-check the official PAYE numbers against what your employer actually deducted.

Worked example: £75,000 PAYE plus £8,000 dividends

A higher-rate professional with a small investment portfolio outside an ISA. This is where the seven-tools problem starts to bite.

Step 1: HMRC's income tax estimator for the salary.

• Personal allowance: £12,570 at 0%
• Basic rate: £37,700 at 20% = £7,540
• Higher rate: £24,730 at 40% = £9,892
• Total income tax on salary: £17,432
• Employee NI: £3,510

Step 2: dividend tax (separate tool).

The personal allowance is already used up on the salary. Dividends sit on top of the salary in the tax stack, so all £8,000 of dividends fall into the higher-rate dividend band - except for the first £500, which is covered by the dividend allowance.

• First £500: 0%
• Remaining £7,500 at 35.75% (higher-rate dividend, 2026/27): £2,681
• Total dividend tax: £2,681

Total income tax bill: £17,432 + £2,681 = £20,113.

HMRC's calculators will get you to roughly this number if you are patient enough to run both tools and stitch the answers together. What they will not tell you:

• If the £8,000 of dividend-paying investments were inside a Stocks and Shares ISA, the dividend tax would be zero. That is a £2,681 saving for moving the holdings into a £20,000-a-year tax-free wrapper.
• A £5,000 pension salary sacrifice would pull £5,000 out of the higher-rate band, saving £2,000 in income tax and £100 in employee NI, and the £8,000 of dividends would still all sit in the higher-rate dividend band (the sacrifice does not change the dividend tax in this specific case because the dividends still sit above £50,270 of taxable income).
• The Personal Savings Allowance for a higher-rate taxpayer is £500, not the £1,000 a basic-rate taxpayer gets. Cross the higher-rate threshold and your savings allowance halves overnight.

The dividend tax calculator handles the salary-plus-dividend stack in one view and shows the ISA-shelter saving directly.

Worked example: £110,000 and the 60% trap

Between £100,000 and £125,140 the effective marginal tax rate hits 62% and HMRC's calculator does not say a word about it. The reader is in the most punitive band in the UK tax code, in pure misled-by-omission territory.

A PAYE worker on £110,000 with tax code 1257L, no salary sacrifice, no other complications.

HMRC's income tax estimator returns:

• Adjusted net income: £110,000
• Personal allowance lost to taper: £5,000 (£10,000 over £100k, divided by 2)
• Remaining personal allowance: £7,570
• Basic rate: £37,700 at 20% = £7,540
• Higher rate: £64,730 at 40% = £25,892
• Total income tax: £33,432
• Employee NI: £4,205

£33,432 is the right number. What HMRC will not tell the reader is what each marginal pound earned above £100,000 actually costs them. The effective marginal rate in that band is 60% in income tax alone - £1.20 of tax on each extra £2 of income, because the £2 of new income is taxed at 40p plus the £1 of newly-taxable personal allowance is taxed at another 40p. Add the 2% employee NI in the band and you are at 62%.

A pension contribution made in this band is the highest-leverage move in the UK tax code. A £10,000 salary sacrifice from £110,000 would:

• Drop adjusted net income to £100,000
• Restore the full £12,570 personal allowance
• Save £4,000 in income tax (40% of £10,000) plus £2,000 from the restored allowance now sheltering £5,000 from 40%
• Save £200 in employee NI
• Add £10,000 (gross) to the pension pot
• Net cost: roughly £3,800 of take-home for £10,000 in the pension

The "effective relief" on that contribution is something like 62%. Few other legal levers in the UK tax code produce a return like this for a higher earner. HMRC's calculator gives you the £33,432 figure and stops. The 60% tax trap calculator shows the sacrifice-to-restore-allowance maths directly, and the income tax calculator guide walks through the timing around bonus season.

Parents in this band face a secondary cliff. Crossing £100,000 of adjusted net income strips access to tax-free childcare and the 30 hours of free childcare in England. For a household with two pre-school children that loss can be worth another £4,000-£5,000 on top of the personal allowance taper, taking the effective marginal cost of staying above £100,000 to something like 80%. None of which HMRC's tools mention.

Worked example: £45,000 self-employed sole trader

A sole trader with £45,000 of net profit (turnover minus allowable expenses). The self-assessment estimator is the right tool here.

HMRC's self-assessment calculator returns:

• Personal allowance: £12,570 at 0%
• Basic rate income tax: £32,430 at 20% = £6,486
• Class 4 NI: £32,430 at 6% = £1,946
• Class 2 NI: nil (abolished for most from April 2024)
• Total: £8,432
• Plus payments on account for the following year: 50% of the prior year bill due 31 January, another 50% due 31 July

For straightforward sole-trader income, the HMRC tool is broadly accurate. What it does not handle well:

• From April 2024 the cash basis is the default for sole traders under HMRC's simplification rules - the estimator does not ask which basis you are using.
• Trading allowance interaction. Anyone with under £1,000 of gross self-employment income can claim the £1,000 trading allowance instead of expenses, and the tool does not prompt this.
• A self-employed worker paying into a SIPP gets basic-rate relief at source and can claim the higher-rate top-up via self-assessment, but the official calculator will not model the SIPP contribution and tell you the saving in advance.
• Making Tax Digital for Income Tax. Sole traders with combined gross income above £50,000 fall into MTD ITSA from April 2026, dropping to £30,000 from April 2027. The estimator does not warn you that MTD compliance is now your problem.
• Loss-making years get poor handling of Class 4 NI loss carry-forward.

The self-assessment estimator is built for the moment you fill in the return, not for in-year planning. By the time it produces a number, the tax year is over and your only optimisation lever left is the pension contribution.

When HMRC's calculator is the right tool

To be fair to HMRC: the official calculators are the correct tool for a defined set of cases. We are not anti-gov.uk. We are anti the gap between what the tools show and what readers assume the tools show.

Use the income tax estimator if you are a single-salary PAYE worker on a standard tax code and want to confirm the in-year figure HMRC has on file. Use the self-assessment estimator if you are a sole trader estimating the bill before the January deadline with no significant pension contributions to model. Use the marriage allowance calculator if you and your partner are working out whether the £1,260 personal allowance transfer makes sense (one earning below £12,570, the other a basic-rate taxpayer). Use the SDLT calculator for the official stamp duty number on a property purchase. Use the CGT real-time tool when you have a one-off gain from a property sale and need to report and pay within 60 days. Use CEST as a starting point for IR35 status, with the caveat that the tool's outputs are not always accepted by tribunals as definitive.

For everything more complicated than that - a salary plus dividends, the 60% trap, salary sacrifice planning, student loan optimisation, Scottish bands plus a UK pension, the lot - reach for a take-home pay calculator built for the integrated picture. Our take-home pay calculator handles salary sacrifice, dividends, student loan plans 1/2/4/5, postgraduate loans, and Scottish bands in one view. It does not do CGT, IHT, or Schedule D self-employment. For those, the relevant HMRC tool (or a proper accountant) is the right call.

HMRC's tools are correct, free, and authoritative. They are also conservative by design and miss the entire optimisation layer that sits above the basic calculation. If you want to know what you owe, HMRC will tell you. If you want to know what you can legally pay, you need something else. Cross-check your tax code against your latest payslip too - the tax code 1257L explainer covers what each digit and letter means and how to spot a wrong code before it costs you a year of overpayment. If the code on your last P60 doesn't match what HMRC has on file, the tax code checker walks through the fix.

Disclosure. This article is general information about how UK tax works, not personal tax or financial advice. Tax rules, allowances, and thresholds change at every Budget and Autumn Statement - figures cited here reflect the 2026/27 tax year and may be superseded. Pension contributions involve investment in regulated products: capital at risk, the value of your pension can fall as well as rise, and the tax treatment depends on individual circumstances. If your situation is more than mechanical, pay a regulated UK accountant or financial adviser for tailored guidance.

Frequently Asked Questions

How accurate is HMRC's tax calculator?

HMRC's income tax estimator is accurate for the slice it covers: single PAYE salary, standard tax code, England/Wales/NI or Scottish bands, current year. If your situation matches that profile, the number it produces is the number HMRC will collect. It becomes less accurate as soon as you add salary sacrifice, dividend income, multiple employments, student loan plan 5, or the £100,000 personal allowance taper - none of which the tool models directly or warns you about.

Does HMRC's tax calculator include National Insurance?

The income tax estimator at /estimate-income-tax does not include National Insurance in its core output. It is, as the name says, an income tax tool. The self-assessment calculator at /self-assessment-tax-calculator does include Class 4 NI for the self-employed but does not always show employee Class 1 NI for PAYE-plus-self-employed mixed cases clearly. To see the combined income tax plus NI bite on a salary, you need to run both numbers and add them, or use a take-home pay calculator that integrates the two.

Can I use HMRC's calculator for self-employment income?

Yes - the self-assessment estimator at /self-assessment-tax-calculator is the official tool for sole traders. It handles trading profit, basic PAYE alongside, and Class 4 NI. It is weaker on the trading allowance, cash-basis vs accrual-basis accounting, pension contributions, and the MTD for Income Tax compliance rules that kick in from April 2026 for sole traders with combined gross income above £50,000. For anything beyond a simple sole-trader case, an accountant pays for themselves on the first year of self-assessment they tidy up.

Why does HMRC's calculator not include salary sacrifice?

HMRC's official position is that it provides tax information, not tax advice. Modelling salary sacrifice would mean telling a worker how much pension contribution would minimise their tax bill, which crosses the line into advice that HMRC does not want to give. The result is a tool that is technically correct but practically misleading: a £110,000 earner running the official tool sees their tax bill but not the £6,000+ saving available from a sensibly sized pension contribution. The conservatism is structural, not accidental.

How do I check if HMRC has my tax code right?

Log into your Personal Tax Account at gov.uk. The current tax code is shown on the homepage, along with the gross-pay assumption HMRC is using and any deductions for benefits in kind, untaxed savings interest, or prior-year underpayments. If the code looks wrong - especially if you have changed jobs, started receiving dividends, or had a significant pay rise - you can update the income estimate directly in the account, which usually triggers a corrected tax code within a few days. Do not wait for the P60 in May to spot a wrong code: a year on the wrong code can mean either a chunky underpayment HMRC will claw back via next year's code, or an overpayment sitting with the Treasury when it could have been in your bank account.