Employer Cost Calculator UK 2025

What Does an Employee Really Cost?

When you hire someone in the UK, the salary you agree is only part of the picture. On top of the gross salary, you are legally required to pay employer National Insurance contributions and, for most workers, employer pension contributions under auto-enrolment. Together, these mandatory costs typically add between 15% and 20% to the headline salary figure, though the exact percentage depends on the salary level and your pension arrangements.

Beyond the statutory requirements, many employers also provide benefits such as private medical insurance, company cars, cycle-to-work schemes, enhanced sick pay, and training budgets. These are optional, but they add to the true cost of employment. For the purposes of this calculator, we focus on the two costs that apply to virtually every employer in the UK: employer NI and pension.

Understanding the full cost of employment matters when you are setting budgets, deciding how many people you can afford to hire, or comparing the cost of an employee against a contractor or freelancer. It is also useful when negotiating salary packages, because the total cost to the business is always higher than the number on the offer letter.

If you run a limited company and pay yourself a salary, these same costs apply to your own pay. Many company directors take a salary at or near the personal allowance to minimise the combined tax and NI burden, then extract further profits as dividends. Understanding how employer NI works helps you make that decision.

Employer NI Explained

From April 2025, employer National Insurance is charged at 15% on all earnings above the secondary threshold of £5,000 per year. This is a notable change from the previous tax year, when the rate was 13.8% and the secondary threshold was £9,100. The combined effect of a higher rate and a lower threshold means that employer NI bills have increased substantially.

For example, on a salary of £35,000, the employer NI calculation works as follows: £35,000 minus the £5,000 threshold equals £30,000 of earnings subject to NI. Multiplying £30,000 by 15% gives £4,500 in employer NI. That is a significant addition to the cost of employment and works out at £375 per month.

The employer NI threshold is separate from the employee NI threshold. Employees start paying their own NI contributions once their earnings exceed the primary threshold, which is £12,570 for 2025/26. Employers begin paying at the much lower £5,000 secondary threshold, which means employer NI kicks in on almost all paid employment.

Certain categories of employee attract reduced or nil employer NI rates. Employees under 21 and apprentices under 25 benefit from a zero rate on earnings up to £50,270 (the upper secondary threshold). Veterans in their first twelve months of civilian employment also have a zero rate up to the same threshold. These reliefs can make a meaningful difference when hiring younger workers or ex-military personnel.

The Employment Allowance, which from April 2025 stands at £10,500, allows eligible employers to reduce their total employer NI bill by that amount each year. Smaller businesses and charities often qualify. However, single-director limited companies where the director is the sole employee are not eligible. If your total employer NI liability is less than £10,500, you effectively pay no employer NI at all.

Auto-Enrolment Pension

Since the completion of the auto-enrolment rollout, most UK employers are required to enrol eligible workers into a workplace pension scheme and make contributions on their behalf. The minimum employer contribution is 3% of qualifying earnings, which is the portion of salary between the lower earnings limit (£6,240) and the upper earnings limit (£50,270) for 2025/26.

The total minimum contribution, including the employee's share, is 8% of qualifying earnings. The employee must contribute at least 5% (before tax relief is applied). Many employers contribute more than the minimum, either as a standard policy or through matching schemes that incentivise employees to save more.

Some employers base their pension contribution on the full gross salary rather than qualifying earnings alone. This is more generous to employees but costs the employer more. When budgeting for the true cost of an employee, check whether your scheme uses qualifying earnings or gross salary as the pensionable pay figure.

Salary sacrifice is an increasingly popular way to structure pension contributions. Under a salary sacrifice arrangement, the employee agrees to reduce their contractual salary, and the employer pays the difference directly into the pension. Because the contribution comes from the employer, neither party pays National Insurance on that amount. This produces NI savings for both sides and is one of the few genuinely win-win arrangements in UK employment tax. However, the reduced salary can affect entitlements that are based on earnings, such as statutory maternity pay and mortgage affordability assessments.

Example Costs

The following examples show the total annual cost to an employer for three different salary levels, assuming a 3% employer pension contribution on gross salary and the 2025/26 employer NI rate of 15% above £5,000.

£25,000 Salary

At a gross salary of £25,000, the employer NI comes to £3,000 (15% of £20,000 above the £5,000 threshold). The 3% pension contribution adds £750. The total cost to the employer is therefore £28,750 per year, or roughly £2,396 per month. The overhead on top of the gross salary is 15%, meaning the employer pays £1.15 for every £1 of gross salary. For a small business, this is an important figure to build into cash flow projections when bringing on a new hire.

£45,000 Salary

On £45,000, employer NI rises to £6,000 (15% of £40,000). The pension contribution is £1,350 at 3%. The total annual cost is £52,350, which works out at £4,363 per month. The overhead percentage is 16.3%. At this salary level, the employer NI alone exceeds the cost of the pension contribution by a factor of more than four, which illustrates how dominant NI is in the overall overhead calculation.

£75,000 Salary

For a £75,000 salary, the employer NI bill is £10,500 (15% of £70,000). The 3% pension contribution adds £2,250. The total cost to employ this individual is £87,750 per year, or £7,313 per month. The overhead is 17%. At this level, the employer NI alone is a five-figure sum and represents a significant budgetary line item. Employers eligible for the Employment Allowance would see this NI bill wiped out entirely, but most businesses paying salaries at this level will have a total NI liability that comfortably exceeds the £10,500 allowance.

The Bigger Picture

These figures represent the bare minimum mandatory costs. Once you factor in employers' liability insurance, recruitment expenses, onboarding costs, equipment, training, and any discretionary benefits, the true cost of an employee can easily reach 125% to 140% of the gross salary. Businesses hiring for the first time are often surprised by the gap between the salary they offer and the total amount that leaves the business each month.

Budgeting for Employment Costs

When building a business plan or departmental budget, it is essential to account for the full cost of each employee rather than just the salary line. A common approach is to apply a simple multiplier to the gross salary. For employers contributing 3% pension and paying standard employer NI at 15% above £5,000, a multiplier of 1.15 to 1.20 is a reasonable rule of thumb for salaries between £20,000 and £100,000.

The multiplier increases slightly as salaries rise, because a greater proportion of the salary falls above the NI threshold. At lower salary levels, the £5,000 threshold shelters a proportionally larger share of earnings from NI. At higher levels, the threshold becomes less significant and the overhead converges towards the combined NI and pension rate.

For businesses eligible for the Employment Allowance, the multiplier drops considerably. A business employing a single worker at £35,000 with the full £10,500 allowance would see its employer NI bill reduced to zero, bringing the total cost to just the salary plus pension. In that scenario, the multiplier is closer to 1.03 (salary plus 3% pension only). As the payroll grows and the allowance is spread across multiple employees, its impact on the per-head cost diminishes.

It is also worth considering the cost trajectory over time. Many employers offer annual pay reviews, and even a modest 3% annual increase in salary feeds through to proportionally higher NI and pension costs. Over five years, compounding salary growth alongside rising statutory costs can increase employment expenditure by 20% to 25% or more above the starting figure. Building a realistic multi-year forecast helps avoid budget surprises.