🇬🇧 United Kingdom · 2026/27
The tax that isn’t on your payslip
On a £45,000 salary, £9,080 is taken before the money reaches you — about 20%. Then you spend what’s left, and more tax comes out of it: an estimated £1,732 a year in VAT and fuel duty, which takes the real share of your income to about 24%. This page shows exactly how that second number is worked out, and what it leaves out.
The half you can see
This part is not estimated. Income tax and National Insurance are computed from the published 2026/27 bands, for a single earner, the same way a payslip does it.
Bands shown are for England, Wales & Northern Ireland. Scotland uses different income-tax bands.
The half you can’t
VAT never appears on a payslip, because it is charged when you spend rather than when you earn. HMRC publishes a standard rate of 20%, with reduced and zero rates for some things — which is why the six numbers below are all different. Tax.cal asks what you spend each month in six categories and applies one effective rate to each.
| Category | Tax.cal assumes | Why |
|---|---|---|
| 🛒 Groceries | 3.3% rough |
Most food sold in a supermarket is not standard-rated in the UK. This small figure is Tax.cal’s assumption about the rest of a typical trolley — household goods, confectionery, alcohol. |
| 🍽️ Eating out & takeaway | 16.7% known rate |
Standard-rated. On a price that already includes 20% VAT, the tax is one sixth of what you hand over. |
| ⛽ Fuel / petrol | 55.0% estimate |
The largest single assumption: fuel duty, plus VAT charged on top of it. It is a share of the pump price, not a published rate, and pump prices move. |
| 🛍️ Shopping & clothing | 15.8% estimate |
Mostly standard-rated, but not all of it — so Tax.cal uses a little under one sixth. |
| 💡 Utilities & bills | 10.0% estimate |
Domestic energy is not charged at the standard rate; other bills generally are. This is a blend. |
| 🎬 Subscriptions & fun | 16.7% known rate |
Standard-rated, so the same one sixth as eating out. |
Applied to the spending the calculator pre-fills at this salary, that comes to:
Why one sixth, not a fifth
A £10 meal that already includes 20% VAT is £8.33 of food and £1.67 of tax. The tax is a sixth of what you hand over, not a fifth of it — a fifth would be the answer if you knew the price before VAT was added, and you almost never do. Tax.cal asks what you actually spend, so it uses the sixth: 16.7%.
The number depends on what you spend
Direct tax is fixed by your salary. Hidden tax is not — it scales with how much of your take-home actually gets spent on taxed things. At £45,000, on the same £9,080 of direct tax:
| Spending across the six categories | Hidden tax a year | Real rate |
|---|---|---|
| £850 a month pre-filled | £1,732 | 24% |
| £1,270 a month | £2,615 | 26% |
| £1,690 a month | £3,505 | 28% |
Rent, mortgage payments and council tax are not in the list, so this is not a question of spending your whole take-home. They are left out because rent and mortgage interest do not carry VAT, and council tax is not charged on what you buy.
Which is the point of typing your own figures in. The pre-filled numbers are a plausible household, not yours.
What the number leaves out
All of these are real, and none of them is counted: council tax, alcohol and tobacco duties, insurance premium tax, air passenger duty, vehicle excise duty, stamp duty, and employer’s National Insurance — which is paid on top of your salary and never shows up anywhere you can see it. Business taxes that end up inside the prices you pay are not counted either, because there is no honest way to attribute them to one person.
Student loan repayments are also left out, on the grounds that they are a debt repayment rather than a tax, even though they come out of the same payslip.
The direction of all of that is one way: the real figure is higher than the one Tax.cal shows, not lower. Where something cannot be estimated honestly, it is left out rather than guessed at.
Two kinds of number
The direct half is precise. Real published 2026/27 brackets and thresholds, checked against known take-home figures.
The indirect half is an estimate, and says so. One effective rate stands in for a whole category, because a real weekly shop mixes things taxed at different rates and Tax.cal has not seen your receipts. Every category carries a known rate, estimate or rough label in the calculator so you can see which parts are doing the guessing.
It does not know your pension contributions, salary sacrifice, other income, or anything you already claim. It is an educational estimate of a total, not a personal tax position — and not tax advice.
Run it on your own numbers
Takes about twenty seconds. Nothing you type leaves your device.
Open the calculatorThe same method runs for eleven countries — see the UK summary, or pick another from the calculator.
Or see the same method applied across all eleven: which country taxes you most.
or go straight to taxcal.siddheshthapa.com
Asked and answered
Why does Tax.cal use 16.7% for VAT and not 20%?
Because VAT is added to a price. A £10 meal that already includes 20% VAT is £8.33 plus £1.67 of tax, so the tax is one sixth of what you hand over rather than a fifth. Tax.cal asks what you spend, not what things cost before tax, so it uses the sixth.
How accurate is the hidden-tax figure?
It is an estimate and is labelled as one. The direct half — income tax and National Insurance — is computed from published 2026/27 bands and is precise for a single earner. The indirect half applies one effective rate to a whole spending category, because a real shop mixes items taxed differently. Each category carries a confidence label in the calculator.
What taxes are left out of the number?
Council tax, alcohol and tobacco duties, insurance premium tax, air passenger duty, vehicle excise duty, stamp duty and employer’s National Insurance are all real and none of them is counted. Student loan repayments are not counted either, because they are not a tax. The figure Tax.cal shows is therefore a floor, not a ceiling.