The verdict in three sentences
A consultancy's biggest leak is unbilled time: 4 to 6 % of revenue evaporates every year for lack of reliable entry. A time-tracking + billing tool costs EUR 25 to 60 per user per month as SaaS, or EUR 20,000 to 40,000 custom-built and integrated with your accounting. The payback comes in under 12 months thanks to +5 points of time recovery and a DSO cut by 4 days.
SaaS vs custom: the 2026 figures
SaaS is fast to switch on; custom pays off over time and integrates natively with your accounting software to remove double entry.
| Criterion | SaaS timesheet | Custom |
|---|---|---|
| Entry cost | EUR 0 to 2,500 | EUR 20,000 to 40,000 |
| Recurring cost | EUR 25 to 60/user/month | EUR 150 to 400/month |
| Annual cost (15 users) | EUR 4,500 to 10,800 | EUR 1,800 to 4,800 after build |
| Timeline | 2 to 6 weeks | 2 to 4 months |
| Accounting integration | Import/export | Native (auto entries) |
| Billing rules | Standard | Bespoke |
Over 4 years and 15 users, SaaS weighs EUR 18,000 to 43,000, versus EUR 27,000 to 59,000 for custom — but custom removes admin hours that SaaS leaves on your plate.
Quantifying unbilled time
Before buying, measure the leak. Here is a 2026 grid for a typical Amsterdam firm.
| Indicator | Before tool | After tool |
|---|---|---|
| Time-recovery rate | 78 % | 83 % |
| Hours logged late (>7 d) | 35 % | 8 % |
| DSO (days to pay) | 58 days | 54 days |
| Billing admin time/month | 22 h | 9 h |
| Billing disputes | 6 %/year | 3 %/year |
These are 2026 order-of-magnitude estimates; the real gain depends on your average daily rate (often EUR 800 to 1,200 in Amsterdam) and your entry discipline.
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Mini case study
Antoine, CFO of a 15-consultant firm in Amsterdam, delivers EUR 2.1M revenue. His time-recovery rate is stuck at 78 %, about 5 % of revenue lost, roughly EUR 105,000 a year. He deploys a custom tool at EUR 32,000 integrated with his accounting. Lifting recovery to 83 % (+5 points) recovers around EUR 105,000 of billable base, of which, prudently, EUR 45,000 to 60,000 actually billed in year one. Add 13 hours/month of admin saved (156 h/year at EUR 45 = EUR 7,000): the tool pays for itself in 7 to 9 months.
FAQ
How much revenue do you really recover? Firms that make entry reliable gain on average +5 points of recovery rate in 2026, i.e. the 4 to 6 % of revenue that was evaporating. On EUR 2M revenue, that is EUR 80,000 to 120,000 of billable base recovered.
Isn't SaaS enough for a small firm? Below 10 consultants, a SaaS at EUR 25-40/user is often the best cost/speed ratio. Custom becomes relevant with accounting double entry or atypical billing rules.
What DSO gain? Automating progress billing cuts DSO by 4 to 6 days on average, freeing tens of thousands of euros in cash for a firm at EUR 2M revenue.
Is accounting integration risky? No if scoped: allow 2 to 3 weeks to connect your accounting software and generate entries automatically, within a 2 to 4 month project.
What maintenance budget? EUR 1,800 to 4,800 per year for a custom tool (hosting, fixes, evolutions), i.e. 12 to 15 % of the build.
Let's scope your project. Give us your headcount, your average daily rate and your accounting software: we will quote a time + billing tool with an indicative budget and timeline. 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.
