Most underpayments are accidental

Are you actually paying minimum wage?

Almost nobody underpays the headline rate on purpose. They get caught by what comes off afterwards — a uniform, a tool deposit, a lift to site, a room above the pub. This checks the rate after the deductions, which is the only test HMRC applies.

The pay period

Gross pay for the period

Hours worked

Include travel between assignments and mandatory training.

Age band

Deductions and charges

Uniform / PPE

Always reduces NMW pay. No exceptions.

Tools

Employer transport

A charge for getting to site counts against you.

Accommodation charged

Only what you charge for employer-provided accommodation.

Days of accommodation

Offset allowance is £10.66 a day; anything above it bites.

One free check per company. Company number and a work email, and the figures run through the same NMW engine we use in payroll, with the full test shown.

The working LIVE

HMRC names the employers who get this wrong.

Underpayment means arrears at current rates, a penalty of up to 200% of the shortfall (source: gov.uk, National Minimum Wage enforcement policy), and publication on the government's naming list. Nearly every case on that list was an accounting mistake, not an intention. A payroll that checks the effective rate on every run simply never gets there.

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The other calculators

Take-home payTax, NI and student loan on a wage Employer costWhat a hire really costs you Holiday pay12.07%, 5.6 weeks, or the 52-week average Auto-enrolmentWho must be enrolled, and for how much Statutory paySSP, SMP, SPP and the rest CIS deductions20%, 30% or gross

Why the deductions matter so much. For NMW purposes your pay is gross pay minus anything deducted for the employer's benefit or required for the job — uniform, tools, PPE, transport you charge for. Accommodation is different again: you may charge up to £10.66 a day (source: gov.uk, National Minimum Wage accommodation offset 2026/27) without it counting, and every penny above that reduces NMW pay. Hours matter too: time spent travelling between assignments, on mandatory training, or waiting on site is working time. This tool computes; it does not advise. Salaried-hours workers with annual averaging are a different regime — take those to an adviser.