The verdict in three sentences
With 2,000 assignment contracts a month across 6 agencies in Brussels, the cost of packaged staffing software depends mostly on user count, while custom software is paid once and fits your processes. Beyond 25 internal users and client-specific billing rules (multipliers, surcharges, bonuses), custom becomes competitive within 3 to 4 years. The key remains clean integration with your payroll provider, Dimona declarations and joint committee (commission paritaire) rules.
Packaged or custom: costs over 5 years
Packaged staffing tools charge a per-user subscription, with paid add-ons for e-signature, worker portals or connectors. Custom software requires an upfront investment and annual maintenance.
| Item (2026 market estimate) | Packaged software | Custom software |
|---|---|---|
| Subscription or build | 80-200 EUR per user per month | 60,000-140,000 EUR |
| 30 users over 5 years | 144,000-360,000 EUR | included |
| E-signature | 1-3 EUR per contract | 1-3 EUR per contract |
| Worker portal and app | add-on 500-1,500 EUR per month | included |
| Payroll and Dimona connector | 5,000-15,000 EUR | 10,000-25,000 EUR |
| Annual maintenance | included in subscription | 10-15% of build |
| Deployment time | 2-4 months | 5-7 months |
For 30 users at 120 EUR a month, the subscription reaches 216,000 EUR over 5 years. A 100,000 EUR build with 12% maintenance comes to about 160,000 EUR over the same period. E-signature stays a variable cost either way: 2,000 contracts at 2 EUR means 48,000 EUR a year, to be negotiated on volume.
The modules that save agencies time
The main gain comes from removing re-keying between contract, timesheet, payroll and client invoice.
| Module | What it automates | Estimated time saved |
|---|---|---|
| Assignment contract | generation, legal clauses, remote signing | 12 min per contract |
| Mobile timesheet | worker entry, client approval | 8 min per timesheet |
| Pay engine | joint committee rates, surcharges, bonuses | 5 min per payslip |
| Client billing | per-client multipliers, grouping | 6 min per invoice |
| Dimona and payroll export | declarations and monthly payroll file | 1 day per month |
| Network dashboard | margin by agency, client, job type | 2 h per week |
In Belgium, each assignment requires a Dimona declaration before work starts, and pay must follow the scale of the user company's joint committee. A mistake repeated across 2,000 contracts quickly turns into back pay claims or social inspection penalties.
Mini case study
Sophie, director of a 6-agency staffing network in Brussels, handles 2,000 contracts and 2,000 timesheets a month. Her teams spend about 20 minutes per assignment across contract, timesheet and invoice, or 667 hours a month. With fit-for-purpose software, the estimate falls to 6 minutes, freeing 467 hours a month. At a loaded hourly cost of 38 EUR, savings approach 17,700 EUR a month, or 213,000 EUR a year. On a 110,000 EUR project, payback lands around 6 months, excluding e-signature.
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FAQ
How much does custom staffing software cost in Brussels in 2026?
As an estimate, budget 60,000 to 140,000 EUR depending on agency count, billing rules and connectors. A 6-agency network with a worker portal often lands between 90,000 and 115,000 EUR.
Do we need to replace our payroll provider?
Not necessarily. The business software can produce pay variables and an export compatible with your social secretariat, which stays in charge of filings. That connector costs an estimated 10,000 to 25,000 EUR.
Is e-signature valid for assignment contracts in Belgium?
Yes, an eIDAS-compliant electronic signature is valid. The contract must be signed no later than when work starts, with a timestamped proof kept on file.
How long to roll out across 6 agencies?
Plan 5 to 7 months for custom software, including a 4 to 6 week pilot in one agency. Rolling out agency by agency limits risk during peak periods.
Can temp workers log hours on mobile?
Yes, through an offline-capable web or mobile app with approval by the client company. Adoption often exceeds 80% after 2 months if logging takes less than a minute.
Let's scope your project. Tell us about your network, contract volume and payroll setup, and we will send a scope, an indicative budget and a rollout schedule. Detailed quote within 48 h. WhatsApp +221 77 596 93 33.
Mohamed Bah
Fondateur, Kolonell
Passionate about digital and entrepreneurship in Africa, Mohamed has been helping Sénégalese businesses with their digital transformation since 2020. Founder of Kolonell, he believes every SME deserves a professional and accessible online présence.
