Invoices and professionals · Indexo Pro, coming soon
Bulk calculation: net pay and cost to the employer for a whole team in 2026
Updated on
Since 1 November 2026, withholding tax on pay has been calculated differently (Royal Decree of 27 September 2026). The calculations on this page still follow the previous rules: for pay received from 1 November, withholding tax and net pay may differ. Update in progress.
Indexo Pro will calculate, in one go, the net pay and cost to the employer for every employee in a CSV file, with the same engine as the free calculator. In the example below, 6 fictitious employees receive €14,768.61 net a month and cost their employer €24,901.10 a month (€348,414 over a year), with the parameters in force on 1 October 2026.
The feature is coded but not yet activated: nothing is on sale, and the calculation for one person stays free, with no limit.
What the bulk calculation will do
- One file, the whole team. You drop in a CSV file (one line per employee): Indexo reads it in your browser and calculates each line.
- The breakdown of each net pay. Employee contributions to the National Social Security Office (NSSO), work bonus, withholding tax (bedrijfsvoorheffing / précompte professionnel), special social security contribution: as on a payslip.
- The cost to the employer. Gross pay, basic employer contributions (25% of gross pay, on 108% for a blue-collar worker), the employer’s share of meal vouchers; over the year, double holiday pay or blue-collar workers’ holiday contributions, and the year-end bonus.
- Totals and export. A table by employee with totals, exportable to Excel (numbers you can use in your formulas), to CSV, or as a PDF report on your firm’s letterhead.
- No line lost. An unreadable line (missing gross pay, unknown status) is flagged with its number, never silently skipped.
Who it is for: HR departments that want to know a team’s cost, payroll managers checking their software, accounting firms running simulations for several clients.
The file format
A text file in CSV format, with the headers on the first line. The separator can be a semicolon (French-language Excel), a comma or a tab. Only the statut and brut columns are required; common Dutch headers (bruto, statuut, kinderen…) and English headers (gross, status, children…) are recognised.
| Column | Contents | Example | Required |
|---|---|---|---|
matricule | Employee identifier: staff number, code or name | T001 | No |
statut | employe (white-collar) or ouvrier (blue-collar) | employe | Yes |
brut | Gross monthly salary under the contract, in euros, for the working time stated | 3000 | Yes |
situation | isole (single), 2rev (married couple or legal cohabitants, two incomes) or 1rev (single income). Default: isole | isole | No |
enfants | Number of dependent children. Default: 0 | 0 | No |
regime | Working time as a % of full-time: 100, 80 (four-fifths), 50 (half-time). Default: 100 | 100 | No |
cp | Joint committee: 200, 124, 302… It sets the indexation and, for JC 200 and JC 302, the pay scale | 200 | No |
cheques_repas | Face value of a meal voucher, in euros per day. 0 or empty: no meal vouchers | 8 | No |
jours_cheques | Meal voucher days per month. Default: 19.17 (230 days a year for 5 days a week) | 19.17 | No |
prime_fin_annee | oui (yes) or non (no): year-end bonus equal to one month’s gross pay. Empty: not counted | yes | No |
classe | Optional, for seniority: pay scale class (JC 200: A, B, C or D; JC 302: category 1 to 9) | A | No |
experience | Optional, for seniority: years of experience recognised by the pay scale | 3 | No |
The full sample file:
matricule;statut;brut;situation;enfants;regime;cp;cheques_repas;prime_fin_annee;classe;experience T001;employe;3000;isole;0;100;200;0;oui;; T002;employe;4000;isole;0;100;200;0;oui;; T003;employe;5000;isole;0;100;200;0;oui;; T004;employe;2324.14;2rev;1;100;200;8;oui;A;3 T005;ouvrier;2900;1rev;1;100;124;8;oui;; T006;ouvrier;2400;2rev;2;80;302;0;oui;;
Worked example: 6 employees
The file above, calculated by the Indexo engine. For example, T001 (single white-collar worker, €3,000 gross) receives €2,261.33 net; they cost their employer €3,750.00 a month (€3,000.00 gross pay and €750.00 employer contributions), and €51,510 over the year with double holiday pay and the year-end bonus.
| Employee | Status and situation | JC | Gross | Net per month | Cost to the employer per month | Cost to the employer per year |
|---|---|---|---|---|---|---|
| T001 | White-collar, single | JC 200 | €3,000.00 | €2,261.33 | €3,750.00 | €51,510 |
| T002 | White-collar, single | JC 200 | €4,000.00 | €2,614.26 | €5,000.00 | €68,680 |
| T003 | White-collar, single | JC 200 | €5,000.00 | €3,051.72 | €6,250.00 | €85,850 |
| T004 | White-collar, couple, two incomes, 1 child | JC 200 | €2,324.14 | €2,174.15 | €3,037.64 | €41,495 |
| T005 | Blue-collar, couple, one income, 1 child | JC 124 | €2,900.00 | €2,593.72 | €3,815.46 | €55,918 |
| T006 | Blue-collar, couple, two incomes, 2 children, 80% | JC 302 | €2,400.00 | €2,073.43 | €3,048.00 | €44,961 |
| Total | 6 employees | €19,624.14 | €14,768.61 | €24,901.10 | €348,414 |
Not included: reductions in employer contributions (first hires, older workers…), workplace accident insurance, occupational health service, social secretariat (payroll provider) fees. Indicative information, not advice.
Your pay data stays with you
As with all Indexo tools, the calculation will run entirely in your browser: the file is sent to no server, nothing is saved, no account. You can therefore use it with real payroll data, without a data processing agreement.
To project this cost over the following years, with expected indexations, see the payroll budget. For a single person, the gross-to-net calculation stays free.
Prepare your file
Choose your spreadsheet’s separator: Indexo shows the expected columns, the example calculated by the engine and a template to copy. The Indexo Pro buttons are visible but not yet active.
The tool could not be displayed. Reload the page (Cmd + Shift + R on a Mac, Ctrl + F5 on a PC).
Frequently asked questions
Is my salary file sent to Indexo?
No. The file is read in your browser and does not leave it. No server receives it, nothing is saved.
Which employees does the bulk calculation cover?
White-collar and blue-collar workers in the private sector, full-time or part-time, with their family situation, dependent children, meal vouchers and year-end bonus. Other statuses (students, flexi-jobs, civil servants) can still be calculated one by one in the calculator.
Does the calculation replace my payroll software?
No. It is an independent estimate, useful for checking amounts or preparing a budget. The official payslips are still those from your social secretariat or your software.
When will the bulk calculation be available?
No date has been set. The feature is coded and tested, then left switched off. The Indexo Pro page is updated with each new feature.
What next?
- Payroll budgetThe team’s cost over one to three years, with expected indexations.
- Indexo Pro, coming soonAll the bulk features in preparation.
- Gross to netThe net of a salary, free of charge.
- Check my payslipA payslip compared with the expected calculation.
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%.
- Instructions administratives : le bonus à l’emploi, NSSO.
- Calcul du précompte professionnel : annexe III de l’AR/CIR 92 et formule-clé 2026, FPS Finance.
- La cotisation spéciale pour la sécurité sociale, NSSO.
- Plafonnement des cotisations patronales à 85 000 € par trimestre, Deg & Partners (secondary source).
- Pécule de vacances : base de la cotisation sur le double pécule, NSSO.
- Administrative instructions 2026/3: holiday contributions for blue-collar workers, 5.57% per quarter and 10.27% through the annual debit notice, on gross pay raised to 108%, NSSO. Cross-checked with: Deg & Partners and Securex: rise to 5.69% then 5.84% announced, Royal Decree not yet published.
- Meal vouchers: Royal Decree of 10 November 2025, maximum value of €10, Belgian Official Gazette. Cross-checked with: the CSC/ACV and Partena Professional.