Indexo School · Lesson 3

What an employee costs: three amounts for one salary

Updated on 26 October 2026

For a white-collar worker on €3,000.00 gross a month, the employer pays about €3,750.00 with basic employer contributions, and the worker receives €2,261.33 net: roughly 60% of the cost.

So one salary has three amounts: the cost to the employer, the gross pay in the contract and the net pay in the account. Here is where the gap comes from.

1. Employer contributions

On top of gross pay, the employer pays its own social security contributions. In the private sector, the basic rate is 25% of gross pay. They are not withheld from pay: the worker does not see them in net pay. The employer pays the NSSO its own share and the share withheld from the worker (13.07% of gross pay).

2. Three amounts, three salaries

Gross salary	Employer social security contributions	Cost to the employer	Worker’s net pay	Share of the cost as net pay
€2,000.00	€500.00	€2,500.00	€1,957.29	78%
€3,000.00	€750.00	€3,750.00	€2,261.33	60%
€4,000.00	€1,000.00	€5,000.00	€2,614.26	52%

Private-sector white-collar worker, single, no children, ordinary month. Cost at the basic employer contribution rate of 25%, without reductions. Indexo engine calculation, parameters in force on 1 October 2026.

The higher the salary, the smaller the share of the cost that ends up as net pay: income tax is progressive (see income tax).

3. What comes on top over the year

Double holiday pay: 92% of one month’s gross pay for a white-collar worker, usually paid before the main holiday.
Often a year-end bonus: it depends on the sector’s joint committee.
Compulsory accident-at-work insurance and the payroll office.
Any benefits: meal vouchers, travel reimbursement, working from home.

The full calculation, for the year and with these items: the employer cost.

4. Contribution reductions

To encourage hiring, the State reduces employer contributions in some cases: a business’s first employees, some low salaries, some groups of workers. The worker’s gross and net pay do not change; only the cost to the employer goes down. See hiring a first employee.

The exercises

Choose an exercise and a level, work it out, then enter your answers. Tick ‘Show the answers’ to see Indexo’s calculation. Teacher: the six-exercise worksheet and its answer key, to print.

The questions

Eight multiple-choice questions. Answer them, then tick ‘Show the answers’ to read the explanations. Teacher: the quiz and its answer key, to print.

Frequently asked questions

Is the real cost higher than in the exercises?

Yes: the exercises keep only the basic employer contribution rate. Over the year, you need to add double holiday pay, any year-end bonus, accident-at-work insurance and other contributions. Conversely, reductions can lower the cost.

Why the basic rate?

It is the rate that applies to all private-sector employers: 25% of gross pay. It makes it easy to compare gross pay, net pay and cost.

What next?

Next lesson: the student jobThe contract, the hours, the solidarity contribution.
For teachersThe six-session sequence, the worksheets and the answer keys.
The test20 points, two versions, the marking scheme and the answer key.

Sources

Parameters in force on 1 October 2026. Each parameter links to its source, the official one where it exists; a secondary source is flagged as such.

Instructions administratives : les cotisations de sécurité sociale, NSSO. Cross-checked with: UCM, Securex and the FEB (via the Walloon Public Service) for the basic employer rate in the private sector: 19.88% basic contribution and 5.12% wage moderation contribution, making 25%.
Pécule de vacances : base de la cotisation sur le double pécule, NSSO.