How much does application maintenance cost: the figure missing from every quote

A quote prices construction and stops there. The next line, recurring annually, is worth 15–25% of initial cost according to an agency publishing it. Where that percentage comes from, what it pays and what happens when nobody budgeted for it.

Application maintenance costs 15–25% of initial development cost each year according to agency Lonestone's published schedule. For an application delivered at €40,000, that is €6,000–€10,000 annually to keep it working before any enhancement you request.

Where the percentage comes from, and what it pays

Lonestone ties maintenance to two precise causes: operating-system compatibility and updates to dependencies, the components others wrote that your application relies on. None adds a feature. A phone receives a new iOS version and the payment screen disappears; an image-processing library releases a security fix and needs replacement. Work exists even if nobody requested anything, while the budget almost never exists because the line was absent from the signed quote.

The broad 15–25% range covers two situations. A simple web application without app stores or hardware to satisfy falls at the bottom. A mobile app in two stores, following Apple and Google rules and remaining compatible with users' phones, reaches the top. Ask your provider which half applies and why.

What no-code charges instead

On a platform, the vendor handles technical maintenance in exchange for a never-ending subscription. Specialist publication nocode.mba estimates a realistic production Bubble budget of $80–$150 monthly after payment processing, email, analytics and paid extensions. Consumption follows success because each request, rule execution and page load uses units. No French no-code agency consulted publishes maintenance rates, because none is needed: the rent already sits in the platform.

Availability costs more than the percentage

A half-day change six months after delivery costs around €250 from a median freelancer, with 2026 TJMètre and Freeland daily rates at €454–€520. The price is bearable; waiting less so. An owner on Reddit (r/smallbusiness, July 2026) says every local agency consulted asks for a large monthly retainer and three months to fix layouts, while they hesitate to pick a marketplace freelancer hoping they will not disappear halfway. Three months for a button: that is maintenance's real cost when someone else must read your own code.

Reduce the line rather than endure it

Three things lower it. First: own the code and explanatory document so another provider can take over without starting over, requiring verification of what is in your name before needed. Second: tests written before code that flag failures during updates rather than letting customers discover them. Third: the ability to perform simple corrections yourself. When an agent team built an application from approved requirements, that document helps prepare a dependency update and the tests to rerun. Its cost depends on incompatibilities encountered and assistant usage; our tests do not guarantee an amount per update. Approval, hosting and external services still need funding within the maintenance budget.

Budget before signing

Add a project-budget line: 20% of the quote annually for five years. A €15,000 build adds €15,000 over that period, as much as construction. If that changes your decision, you needed it before signing rather than the second failure. Ask what maintenance covers, included hours, intervention deadline and what happens beyond quota. Ary Studio, publishing its tiers, announces thirty days' post-launch support for critical fixes: a period, not a subscription, leaving month thirteen unresolved. Our ten agency quotes compared give starting amounts for this percentage, and the quote is not the cost details other post-signature gaps.