The verdict in three sentences
Application maintenance (TMA) for a web app costs 15-22% of build cost per year, i.e. 7,000-30,000 EUR/year for a 50,000-150,000 EUR app. It covers four items: fixes, enhancements, monitoring and security, on top of EU hosting (100-600 EUR/month). The right call is between a predictable fixed-fee TMA and time-and-materials at a 500 EUR day rate.
How much TMA costs in 2026
The 15-22% rate varies with criticality, pace of change and required SLA level.
| Build cost | TMA at 15%/yr | TMA at 22%/yr | Profile |
|---|---|---|---|
| 50,000 EUR | 7,500 EUR | 11,000 EUR | Simple app, few changes |
| 90,000 EUR | 13,500 EUR | 19,800 EUR | Active business app |
| 120,000 EUR | 18,000 EUR | 26,400 EUR | Critical app, high SLA |
| 150,000 EUR | 22,500 EUR | 33,000 EUR | Complex platform |
These 2026 order-of-magnitude figures exclude hosting and large enhancement projects billed separately.
The 4 TMA items and SLA tiers
A serious TMA details what it covers; otherwise you pay for a vague retainer.
| Item | What it covers | Typical share | |
|---|---|---|---|
| Corrective | Bugs, production incidents | 25-35% | |
| Evolutive | Small improvements, tweaks | 25-40% | |
| Monitoring | Alerts, uptime, supervision | 15-25% | |
| Security | Updates, patches, dependencies | 15-25% | |
| SLA tier | Coverage | Relative cost | Best for |
| Best effort | Business hours | Base | Internal app |
| Standard | Response < 4 business hrs | +20-40% | Business app |
| Extended | Response < 1 hr, 12/7 | +50-80% | Customer app |
| 24/7 | Permanent on-call | 2x and up | Critical/e-commerce app |
EU hosting adds 100-600 EUR/month depending on load and redundancy; a 24/7, high-availability need pushes toward the top of the range.
Mini case study
Ms. Leroy, CTO of an e-commerce SME in Nantes, runs an application with a 110,000 EUR build cost. She hesitates between a fixed-fee TMA and time-and-materials at a 500 EUR day rate.
On T&M, she historically consumes ~5 days/month (fixes + enhancements), i.e. 2,500 EUR/month = 30,000 EUR/year, with no guaranteed response time. The fixed-fee TMA at 19% of build comes to 20,900 EUR/year, standard SLA included, plus 300 EUR/month of hosting (3,600 EUR). Fixed-fee total: 24,500 EUR/year, with a response commitment. She saves ~5,500 EUR/year and gains predictability by switching to the fixed fee.
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FAQ
Why pay for TMA if the app works?
Because an unmaintained application accumulates security flaws (outdated dependencies), browser incompatibilities and technical debt. Security TMA (15-25% of the budget) is essential, even with no new features.
Fixed-fee or time-and-materials?
The fixed fee gives predictability and a guaranteed SLA, ideal when volume is stable. T&M at a ~500 EUR day rate suits irregular needs, but without a response commitment.
What exactly does 24/7 SLA cover?
Permanent on-call with intervention outside business hours, essential for e-commerce or a critical app. It typically doubles the monitoring cost versus best effort.
Is hosting included in TMA?
Rarely. Budget 100-600 EUR/month of EU hosting on top, depending on load, redundancy and compliance needs (personal data).
Is the 15-22% rate fixed?
No, it is a 2026 benchmark. A critical app with a fast pace of change and high SLA can exceed 22%; a stable, low-demand app can drop toward 12-15%.
Let's scope your project. Give us your application's build cost, your desired SLA level and your pace of change, for a fixed-fee TMA of 7,000-33,000 EUR/year. 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.
