The salary in the job advert is not what a driver costs. On top of gross pay sits employer National Insurance - a second payroll charge that scales with every pay rise, every bonus and every new starter. The 2025 to 2026 rates and thresholds from HMRC set the numbers, and they belong in every fleet’s costing model.
For 2025 to 2026, employer Class 1 National Insurance contributions are charged at 15% on earnings above the secondary threshold, which is £96 per week, £417 per month or £5,000 per year. Everything an employee earns above that line attracts the 15% employer charge; nothing below it does. For a driver on £35,000 a year, the employer NICs alone come to thousands of pounds on top of the gross salary - the difference between the pay offer and the true cost of the seat. The rates table also shows the employee-side structure, but it is the employer’s 15% that lands on the business.
The same guidance publishes upper secondary thresholds that cut employer NICs for specific groups: earnings up to £967 per week - £4,189 per month or £50,270 per year - attract relief where the employee is under 21, an apprentice under 25, or a qualifying veteran. For an industry that says it wants young blood, the under-21 and apprentice thresholds are the financial expression of that policy: a twenty-year-old driver apprentice costs markedly less in employer NICs than a forty-year-old on the same gross pay. Freeport and Investment Zone upper secondary thresholds, set at £481 per week, extend similar treatment in those designated areas. The relief categories have conditions - the guidance’s tables and notes carry the detail - but the payroll system applies them automatically once the employee’s category letter is right, which is why the category letter on every payroll record is worth a periodic audit.
Behind every employer-NI calculation sits a category letter, and the guidance’s tables are organised by those letters for a reason: the letter determines which rate and which threshold applies to each employee. Standard employees sit in the main category; the under-21, apprentice, veteran and investment-zone categories carry their own letters and their own upper secondary thresholds. The table in the rates guidance shows the employer charge at 15% across the standard categories above the secondary threshold, with the relief categories carrying 0% up to their upper thresholds. When a driver’s twenty-first birthday passes, or an apprentice completes, the letter must change - and a payroll that misses the change overpays silently or underpays until HMRC asks. An annual letter-by-letter review of the driver roster is cheap insurance.
The transport-office use of these numbers is simple: cost every seat at gross pay plus employer NICs at 15% above the threshold, minus any relief the driver’s category attracts, before deciding what the business can offer. The same arithmetic runs in reverse for agency comparisons - the agency rate looks different once the employed alternative is costed properly, NICs included - and for the annual pay review, where a headline percentage increase carries a further 15% on the portion above the threshold. Payroll is usually the largest single cost in a haulage business after fuel, and the employer-NI line is the part of it that never appears in the advert. The rates and thresholds change with tax years; the current year’s page is the only one that counts.
Where these numbers earn their keep most often is the annual pay review. A four per cent rise on a driver’s salary is not four per cent on the cost line: the portion above the secondary threshold carries employer NICs at 15%, so the true cost of the rise is the gross increase plus its NICs. Run the same arithmetic across forty drivers and the pay round’s real price emerges - which is the number the board actually needs. The fleets that get pay negotiations right bring both figures to the table: what the driver sees, and what the seat costs. The rates guidance is updated every tax year, so the costing model’s inputs need refreshing each April alongside the payroll software update.
None of this requires a payroll department; it requires that whoever runs the numbers uses the current year’s rates and thresholds, audits the category letters, and costs seats honestly. The guidance page does the arithmetic’s inputs; the fleet only has to look them up each April.