Annual Web App Maintenance (TMA) Cost in 2026

The verdict in three sentences

Application maintenance (TMA) for a web app costs, in 2026, between 15 and 20 % of the build budget per year, i.e. 6,000 to 16,000 EUR/year for a project delivered at 40,000 EUR. It covers three areas: bug fixes, version upgrades (frameworks, dependencies, security) and small functional evolutions. Not budgeting for it means accepting technical debt that doubles the cost of a rebuild within 3 to 4 years and leaves security holes open.

What maintenance really covers

Serious maintenance is not just a hotline. It combines corrective work (blocking and minor bugs), preventive work (security updates, version upgrades) and evolutive work (adjustments and small features). Pricing depends on the SLA (guaranteed response and fix time) and the criticality of the app.

For a 40,000 EUR project, an 18 % maintenance rate is 7,200 EUR/year, i.e. 600 EUR/month of smoothed budget.

Monthly retainer vs pay-per-ticket

Two models dominate the French market in 2026. The monthly retainer offers a predictable budget and a firm SLA; pay-per-ticket bills consumed hours, more flexible but unpredictable.

The cost of no maintenance is the highest: an unpatched dependency, an exploited vulnerability, an exposed GDPR database can cost far more than a year of maintenance.

Mini case study

Julien, IT director of a services SME in Paris, runs a customer-management web app delivered at 45,000 EUR. Without maintenance in year one, he accumulates 3 blocking bugs (2 days of degraded service each) and a dependency vulnerability. He switches to a retainer at 750 EUR/month (9,000 EUR/year, i.e. 20 % of build) with an 8 h SLA. Result: downtime divided by 5, upgrades kept current, and an avoided cost estimated at 15,000 EUR (lost operations + emergency remediation). Maintenance pays for itself within the first year.

FAQ

What percentage of budget should I plan for maintenance?

Plan 15 to 20 % of build cost per year in 2026. For a critical high-traffic app, go up to 20-25 % to cover a fast SLA.

What is the difference between corrective and evolutive maintenance?

Corrective fixes what is broken (bugs, vulnerabilities); evolutive adds or adjusts features. Good maintenance reserves a monthly quota of evolutive hours.

What does a 4-hour SLA cover?

It guarantees acknowledgement of a blocking incident within 4 business hours, with a fix target within 8 to 24 h. Expect a 20 to 40 % premium over a 48 h SLA.

Can I suspend maintenance to save money?

Not advised: technical debt builds up (obsolete dependencies, vulnerabilities) and a catch-up after 2 years often costs 30 to 50 % of a rebuild.

Are version upgrades really necessary?

Yes. Frameworks and libraries publish regular security patches; staying on an unsupported version exposes you to vulnerabilities and blocks future evolutions.

Let's scope your project. Describe your application (stack, criticality, traffic) and we will propose a retainer with a fitting SLA, from 400 EUR/month. Detailed quote within 48 h. WhatsApp +221 77 596 93 33.