The verdict in three sentences
An in-house team of two developers and a lead in Paris costs EUR 230,000 to 290,000 a year fully loaded, versus EUR 80,000 to 150,000 a year with an agency for 100 to 180 development days. Insourcing only pays off above roughly 350 to 400 development days a year, sustained over time. Below that, the hybrid model, a salaried tech lead steering an agency, gives the best balance of product control, cost and continuity.
What an in-house team in Paris really costs
Gross salary is only the starting point. You must add employer social charges (about 42 % of gross for a French executive), hardware, licences, training and the cost of hiring itself.
| Item | Annual gross salary 2026 | Annual loaded cost | Note |
|---|---|---|---|
| Experienced full-stack developer (4 to 6 years) | EUR 47,000 to 58,000 | EUR 66,000 to 82,000 | Most sought-after profile |
| Lead developer or architect | EUR 67,000 to 80,000 | EUR 95,000 to 114,000 | Essential for architecture |
| Tools, licences, dev cloud, hardware | n/a | EUR 4,000 to 8,000 | Per year for the team |
| Training and tech watch | n/a | EUR 3,000 to 6,000 | 2 to 4 days per person |
| Recruitment agency fee | n/a | 18 to 25 % of annual gross | EUR 10,000 to 20,000 per hire |
| Total team of 3, excluding hiring | n/a | EUR 230,000 to 290,000 | 2026 order of magnitude |
Hiring time weighs as much as budget: allow 3 to 6 months between opening the role and the person starting, including a 1 to 3 month notice period. Once on board, each developer produces about 170 to 180 effective development days a year, after holidays, meetings, support and training. The team of three therefore delivers around 520 days, putting the in-house day at EUR 450 to 560, provided the team is fully busy all year.
Agency cost by volume of days
With an agency, you pay for the days consumed. The day rate of a serious French agency sits between EUR 550 and 800 excl. VAT in 2026, depending on seniority and specialty.
| Annual volume | Day rate EUR 550 | Day rate EUR 650 | Day rate EUR 800 |
|---|---|---|---|
| 100 days | EUR 55,000 | EUR 65,000 | EUR 80,000 |
| 140 days | EUR 77,000 | EUR 91,000 | EUR 112,000 |
| 180 days | EUR 99,000 | EUR 117,000 | EUR 144,000 |
| 250 days | EUR 137,500 | EUR 162,500 | EUR 200,000 |
| 370 days | EUR 203,500 | EUR 240,500 | EUR 296,000 |
| 500 days | EUR 275,000 | EUR 325,000 | EUR 400,000 |
The break-even maths is simple: an in-house team at EUR 260,000 divided by an average day rate of EUR 700 gives about 370 days. As long as your roadmap stays below that volume, the agency costs less, even at a high day rate. Above it, and if demand is stable over several years, insourcing makes financial sense.
Three models compared on the criteria that matter
| Criterion | 100 % in-house team | Agency only | Hybrid (in-house lead + agency) |
|---|---|---|---|
| Annual cost for 150 days of need | EUR 230,000 to 290,000 | EUR 85,000 to 125,000 | EUR 135,000 to 180,000 |
| Time to start | 3 to 6 months | 2 to 4 weeks | 2 to 4 weeks on the agency side |
| Attrition risk | High: developer turnover of 15 to 20 % a year | Carried by the agency | Moderate: a single critical role |
| Control of code and product | Full | Depends on contract and documentation | Strong, the lead approves every delivery |
| Volume flexibility | Low | High | High |
| Rare skills (security, DevOps, mobile) | Must be hired | Included in the agency team | Called on as needed |
The hybrid model answers the main fear of executives: losing knowledge of their own system. The salaried lead holds the access rights, sets the architecture, reviews code and arbitrates priorities. The agency provides production capacity and specialist profiles when needed. Three safeguards make this model robust: code hosted in a Git repository owned by your company, transfer of intellectual property rights written into the contract, and a reversibility clause with up-to-date documentation.
Mini case study
Isabelle, CEO of a medical equipment distributor in Nanterre (85 employees), sees her hospital order management application becoming strategic. Her real need is 140 development days a year.
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- In-house team of 3: EUR 255,000 a year, plus EUR 30,000 of hiring costs in year one, so EUR 285,000. Capacity of 520 days, more than 350 of them without a priority use.
- Agency only at EUR 700 a day: 140 × 700 = EUR 98,000.
- Hybrid: salaried lead at EUR 105,000 loaded, who steers and delivers 60 development days, plus 80 agency days at EUR 700, i.e. EUR 56,000. Total EUR 161,000.
She picks the hybrid model: EUR 94,000 saved per year versus the in-house team (EUR 124,000 in year one), and system knowledge stays in the company for EUR 63,000 more than agency only.
FAQ
From what volume should you insource?
Above roughly 350 to 400 development days a year, sustained, the in-house team is cheaper per day (EUR 450 to 560 versus EUR 550 to 800 at an agency). Below that, you are paying for idle capacity.
How long does it take to hire a lead developer in Paris?
Allow 3 to 6 months between opening the role and the actual start date. A recruitment firm charges 18 to 25 % of annual gross salary, i.e. EUR 12,000 to 20,000 for a lead.
Doesn't the hybrid model create friction?
Yes, if roles are vague. The in-house lead sets the architecture and approves deliveries, the agency works in 2-week sprints. A one-hour weekly meeting is enough in most cases.
How do you avoid depending on the agency?
Require the code in a Git repository in your name, transfer of rights, architecture documentation and a reversibility clause. An end-of-mission knowledge transfer costs EUR 8,000 to 20,000 excl. VAT.
What does losing an in-house developer cost?
With 15 to 20 % annual turnover, plan for 2 to 4 months of lost capacity plus hiring. On a team of 3, one departure means EUR 25,000 to 45,000 of hidden cost.
Let's scope your project. Send us your roadmap and estimated annual development volume: we will price the agency scenario and the hybrid scenario, with an indicative budget and start date. 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.
