The verdict in three sentences
Untracked time is lost revenue: a consulting firm that fails to capture billable time leaves 10-15 % of margin on the table every month. A SaaS licence (Harvest, Clockify, Toggl) at EUR 20-60 per user per month suffices for a small firm, but custom software at EUR 30,000-75,000 pays off once per-engagement billing and accounting integration matter. The decision rests on captured billable time, not licence price.
Build vs SaaS: the 2026 cost comparison
A SaaS time-tracker deploys fast but often disconnects your billing, CRM and accounting. Custom links time, engagement, invoice and accounting export in a single flow.
| Criterion | Custom build | SaaS (Harvest/Clockify) |
|---|---|---|
| Upfront cost | EUR 30,000-75,000 | EUR 0-1,500 |
| Recurring cost | Maintenance 12-15 %/yr | EUR 20-60/user/month |
| Time to deploy | 3-5 months | 1-2 weeks |
| Per-engagement billing | Native, automated | Basic |
| Accounting integration | Full (audit-file export) | Via connectors |
| Engagement profitability tracking | Real time | Limited |
| Cost at 20 users over 3 yrs | EUR 45,000-100,000 | EUR 14,000-43,000 |
At 20 consultants and EUR 40/user/month, SaaS costs EUR 9,600 per year, or EUR 28,800 over 3 years. A custom build at EUR 60,000 plus 13 % maintenance amounts to around EUR 83,400 over 3 years. Pricier upfront, but the margin gain repays it quickly.
Captured billable time: the real margin lever
Licence cost is marginal against the revenue recovered when you stop losing untracked or under-billed hours.
| Indicator | Before custom tool | After custom tool |
|---|---|---|
| Billable time capture rate | 72 % | 85 % |
| Lost hours/consultant/month | 22 h | 6 h |
| Invoice issuance delay | 18 days | 4 days |
| Billing disputes | 9 % | 3 % |
| Additional revenue/consultant/month | - | +EUR 2,340 |
Gaining 13 points of billable time at a EUR 900 day rate represents around EUR 2,340 in extra revenue per consultant per month, with no extra work.
Mini case study
Sarah, COO of a 22-consultant firm in Amsterdam, sees a 72 % billable-time rate and invoices issued 18 days late. She invests EUR 62,000 in a custom time/billing tool, delivered in 4 months, maintenance 13 % (EUR 8,060/year). Capture rises to 85 %, about EUR 2,340 in extra revenue per consultant per month. Across 22 consultants that is over EUR 51,000 monthly, more than EUR 615,000 per year. The investment pays back in about a month.
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FAQ
How much does custom time/billing software cost for an Amsterdam consulting firm in 2026?
Between EUR 30,000 and 75,000 depending on scope (time entry, per-engagement billing, profitability tracking, accounting export). A core foundation sits around EUR 32,000-45,000.
Isn't SaaS enough?
For a firm under 8 consultants, yes. Beyond that, the disconnect between time, billing and accounting creates losses that quickly exceed the cost of custom.
What is the deployment timeline?
From 3 to 5 months: 3 weeks of scoping, 2-3 months of development, then accounting integration and training. Time entry can be live by month two.
How do we measure the billable-time gain?
By tracking the capture rate before/after. Moving from 72 to 85 % at a EUR 900 day rate is around EUR 2,340 in extra revenue per consultant per month.
Does the tool integrate with my accounting?
Yes, custom exports the standard audit file and connects to your accounting software, cutting re-entry and billing errors.
Let's scope your project. Tell us your headcount, average day rate and priorities (per-engagement billing, profitability tracking, accounting export), and we will quantify the expected margin gain. 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.
