Umbrella Companies, Explained: Where Every Deduction Goes

Every line sums exactly to the assignment income — the umbrella company calculator re-solves the waterfall for any day rate, margin or pension percentage, and shows the same itemisation live. On this example, employer costs alone take £14,700.78 off the assignment income before your gross pay is worked out. That is the number most contractors have never seen, and it is the reason a £500 day rate feels like a £94,000 salary rather than a £110,000 one.

Why the waterfall is circular — and why that matters

Employer National Insurance is 15% of your gross pay, but your gross pay is what is left after employer National Insurance is deducted. The calculation is circular, and the only honest way to do it is to solve it so the lines reconcile exactly — which is what the calculator does. Any umbrella quote that does not show its working is asking you to trust a number that cannot be checked. Ask for the waterfall: assignment rate, margin, employer NI, levy, pension, gross, tax, NI, net. If any line is missing, the missing money is being hidden, not saved.

The margin, the levy, and the comparisons that matter

The margin is the only line the umbrella keeps for itself — typically £15 to £30 a week. On this example it is £1,100.00 a year, barely 1% of the assignment income. The Apprenticeship Levy is the line to watch: 0.5% of the pay bill, which some umbrellas pass on and some do not. On this example it would cost £468.96 a year and cut take-home pay to £64,956.43 — small, but it should be itemised, not buried. When you compare umbrellas, compare the margin and the take-home figure, not the headline rate: two umbrellas quoting the same day rate can differ by hundreds of pounds a year on the levy and pension lines alone.

And compare umbrella against the alternatives honestly. A limited company outside IR35 nets more on the same contract — see the IR35 calculator — but carries admin, accounting costs and status risk. A sole-trader route is simpler but has no employer pension and no SSP safety net — see the self-employed tax calculator. Umbrella is the low-admin middle: you pay for someone else to run payroll, and the price is the margin plus the employment costs you would pay as an employer anyway.

Choosing an umbrella: what to compare

There are hundreds of umbrella companies, and they differ on exactly three things that matter: the margin, whether they pass on the Apprenticeship Levy, and how they handle pension. Everything else — the app, the onboarding, the "same-day pay" promise — is cosmetic. Ask each one for a worked example on your day rate, with every line itemised, and compare the take-home figures, not the marketing. A margin of £15 a week against £30 a week is £780 a year; the levy is worth a few hundred more; pension handling can be worth more still if one umbrella enrols you at 3% and another at the minimum with a different qualifying-earnings treatment.

Accreditation is the other filter. The Freelancer and Contractor Services Association (FCSA) accredits umbrellas against a code of compliance, and membership is a meaningful signal — not a guarantee, but a check that someone independent has looked at the books. Avoid any umbrella that cannot explain its deductions in writing, that pays you through a loan scheme, or that offers to "maximise" your take-home by routing pay through expenses: those are the arrangements HMRC unwinds years later, and the bill lands on you, not the umbrella. Boring, itemised and slightly expensive is what a good umbrella looks like. The calculator gives you the numbers to hold any umbrella to account.

The payslip test: reading your first umbrella payslip

The fastest way to judge an umbrella is not its website — it is your first payslip. A compliant payslip shows the assignment income at the top, then every deduction as its own line: employer NI, the Apprenticeship Levy, employer pension, the margin, and then your gross pay, your tax, your employee NI, your employee pension, and your net pay. Every line should reconcile: the lines above gross pay should add up to the assignment income, and the lines below gross pay should add up to gross minus net. If any line is missing, merged into a catch-all, or labelled vaguely — "employment costs", "admin", "other deductions" — that is a warning. Compliant umbrellas itemise because the law requires it; non-compliant ones hide behind vague labels because the detail would not survive scrutiny.

There are two numbers to check on that first payslip. The first is the margin: it should be the figure you were quoted, usually a fixed weekly or monthly amount, and it should not change without notice. If the margin on the payslip is higher than the quote, ask why — in writing. The second is the holiday pay: umbrella workers accrue holiday pay at 12.07% of hours worked, and some umbrellas roll it into the hourly rate ("rolled-up holiday pay") while others hold it and pay it when you take leave. Both are legal if done transparently, but rolled-up pay must be shown as a separate line, and it must be genuinely additional to your pay, not carved out of it. If your payslip shows no holiday pay line at all, ask where it is. The umbrella company calculator shows the full waterfall for your day rate, so you can compare it line by line with the payslip you actually receive — and if the two do not match, the payslip is the one that is wrong.

Red flags

Three things should make you walk away. First, a payslip that shows a single "deductions" line with no breakdown. Second, any scheme that promises to pay you mostly as something other than salary — loans, expenses, offshore arrangements — to dodge tax: these are the disguised-remuneration schemes HMRC pursues years later, with interest. Third, a margin far below the market: if an umbrella charges £5 a week when everyone else charges £25, the difference is coming from somewhere, and it is not generosity. Reputable umbrellas are boring, itemised and slightly expensive. That is the point.

The one thing to remember about umbrellas is that the waterfall is not negotiable — it is arithmetic.

Assignment income in, employer costs out, margin out, and what is left is your gross pay: every line is fixed by the rates, and the only number anyone can choose is the margin. So when two umbrellas quote different take-home pay for the same day rate, one of them is not doing the maths the other one is — and the one quoting more is usually the one leaving something out. The payslip test settles it: every deduction on its own line, every line reconciling to the assignment income. Run your day rate through the umbrella company calculator first, then compare the payslip you actually receive line by line. If they do not match, the calculator is not the one that is wrong.

Figures from the 2026/27 rates, last checked against GOV.UK on 5 November 2026. See all the rates on UK tax rates 2026/27. Next in this series: IR35 in plain English: inside vs outside, with numbers.