The true cost of hiring an employee in the United Kingdom
Reviewed by Mellow Editorial Team, HR & payroll content team
Hiring an employee in the UK costs considerably more than the salary you agree with them. Once you add employer National Insurance, pension contributions, and other statutory obligations, the real cost typically runs 20–25% above the headline wage.
Employer National Insurance
Every time you pay an employee, you owe employer National Insurance Contributions (NICs) on top of their gross salary. The rate is 13.8% on earnings above the secondary threshold (category A employees).
So if you hire someone on a £35,000 salary, you are not paying £35,000 — you are paying £35,000 plus roughly £4,830 in employer NICs alone (13.8% applied to earnings above the secondary threshold). The exact figure depends on where their earnings sit relative to the threshold, but the principle is straightforward: budget for an extra 13.8% on the bulk of any salary.
This is a cost the employee never sees on their payslip. It sits entirely with you as the employer.
Auto-enrolment pension contributions
If your employee is eligible for auto-enrolment — broadly, aged 22 to state pension age and earning above the earnings trigger — you must enrol them into a qualifying workplace pension scheme and contribute a minimum of 3% of their qualifying earnings.
The employee contributes a minimum of 5%. That is their money, not yours, but you are still responsible for administering the scheme, deducting contributions accurately, and paying them to the pension provider on time.
On a £35,000 salary, your 3% employer pension contribution adds roughly £1,050 per year in direct cost (subject to the qualifying earnings band). Small but real, and it compounds across a team.
Statutory leave and sick pay
The law guarantees employees 5.6 weeks of paid annual leave — that is 28 days including bank holidays for someone working five days a week. You are paying for time when no productive work is being done. This is not an optional benefit; it is a floor.
On top of that, Statutory Sick Pay applies when employees are too ill to work, and statutory family leave payments (maternity, paternity, adoption, shared parental) apply when the relevant circumstances arise. Some of these costs are funded partly through HMRC mechanisms, but the administrative burden and the cost of covering absent staff is yours.
When you model the true cost of a hire, divide the annual salary by the actual working days available — after leave — to understand the real daily rate you are paying for productive time.
Payroll administration and compliance
Running payroll in the UK is not a one-off task. Under Real Time Information (RTI), you must submit a Full Payment Submission (FPS) to HMRC on or before every payday. Miss a submission and HMRC can charge penalties.
At the end of the tax year you must issue a P60 to every employee still on your books by 31 May. If you provide any taxable benefits in kind — a company car, private medical insurance, interest-free loans above the de minimis threshold — you must report them on a P11D by 6 July and pay the associated Class 1A NICs.
These deadlines do not flex. The cost here is time, potential penalty exposure, and, for most employers, either payroll software or an outsourced payroll provider. Factor that in.
The Employment Rights Act 2025 and day-one rights
The Employment Rights Act 2025 extended a number of rights to apply from day one of employment, rather than after a qualifying period. This changes the risk calculation when you hire. Protections that previously required months of service now apply immediately, which means the cost of a poor hire — in terms of process, potential claims, and management time — has increased.
This does not mean you should be reluctant to hire. It does mean you should be deliberate: write a clear job description, run a structured process, and document your decisions. Prevention is cheaper than resolution.
Putting the numbers together
For a rough but honest estimate, take the agreed gross salary and add:
- 13.8% for employer NICs (applied to earnings above the secondary threshold)
- 3% for minimum employer pension contributions
- A notional allowance for annual leave (5.6 weeks of paid non-productive time)
- Payroll administration costs
- Any benefits you offer beyond the statutory floor
On a £40,000 salary, the total employer cost before benefits and admin commonly sits between £46,000 and £50,000 once NICs and pension are included. Add benefits, recruitment fees, equipment, and onboarding time and the real first-year cost is higher still.
None of this should deter a hire that makes commercial sense. It should simply inform what you offer, how you budget, and how you structure your payroll process across your workforce so there are no surprises.
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