When an Indian SMB owner asks a developer "what will this app cost", the answer almost always covers design, coding and testing through to launch day. What it rarely covers is the bill that starts arriving the month after go-live: hosting, security patches, app store renewals, bug fixes and the small features users ask for once they start actually using the product. This is the budget line that catches most first-time software buyers off guard, and it is worth planning for before you sign a development contract, not after you get the first renewal invoice.
Why maintenance costs more than people expect
Across the software industry, the benchmark that comes up again and again is that annual maintenance runs somewhere between 15 and 25 percent of what it cost to build the system in the first place. Industry benchmarks across consultancies, technology vendors and academic research converge consistently on the figure that ongoing software maintenance typically runs 15 to 25 percent of the original development cost every single year the software stays in use. For mobile apps specifically, the number tends to sit a little higher: industry benchmarks converge on roughly 20 to 25 percent of the original mobile development cost annually, largely because Apple and Google push frequent OS updates that force compatibility changes.
This is not a one-off adjustment either. The more common long-term pattern is that maintenance cost as a percentage of original development cost tends to rise again in later years, often in years four through seven, as technical debt accumulates and the original development team's familiarity with the system fades. Several industry estimates also point to a wider pattern across the full lifetime of a system: IEEE research shows that 60% of total software cost occurs during the maintenance phase, with only 40% going to initial development. The precise split varies by source, but the direction is consistent: the build is only the opening cost, not the total one.
For budgeting purposes, a simple rule works well enough at the planning stage. If a web application costs roughly ₹10 lakh to build, a reasonable annual maintenance allowance is ₹1.5–2.5 lakh. A ₹25 lakh ERP-style system would need roughly ₹3.75–6.25 lakh a year set aside for upkeep. These are planning ranges, not quotes, but they are a far more realistic starting point than assuming the build cost is the end of the spending.
What actually falls under "maintenance"
Maintenance is not just fixing bugs. It typically covers four overlapping categories:
- Corrective work: fixing defects that surface once real users are on the system.
- Adaptive work: keeping the software working as its environment changes, including operating system updates, browser changes, third-party API changes and new regulatory requirements.
- Perfective work: small usability and performance improvements based on how people actually use the product.
- Preventive work: refactoring and dependency updates done proactively to avoid bigger failures later.
Hosting and infrastructure costs sit alongside this and scale with usage. A low-traffic internal tool on shared or modest cloud hosting costs very little to run month to month, but a customer-facing app with growing transaction volumes will see its hosting bill rise in step with adoption, independent of the maintenance contract itself.
The store and platform fees people forget
If your project includes a mobile app, there are fixed platform costs that recur every year regardless of how much custom work is done:
- Apple Developer Program: Apple charges $99 a year, required to publish on the App Store and use TestFlight for beta testing. This is billed per account, not per app, so one membership covers every app your business publishes.
- Apple Developer Enterprise Program: a separate $299-a-year tier, but this is for proprietary internal apps distributed to your own employees rather than public App Store listings, so most SMBs building a customer-facing app will not need it.
- Google Play Console: a one-off $25 registration fee, paid once for the life of the account rather than annually.
These figures are small on their own but worth budgeting explicitly, since they are easy to overlook when a quote focuses only on development hours, and a lapsed Apple membership will pull a live app off the App Store until it is renewed.
GST and contracting for ongoing support
Whatever shape your maintenance arrangement takes, whether a retainer, an annual maintenance contract (AMC), or ad-hoc time-and-material support, it is taxed the same way as the original development work. Software services attract 18% GST when the customer is in India, and this applies equally to AMC invoices and support retainers as it does to the initial build. If your vendor is overseas or you are commissioning development for export, the rate drops to 0% when the service is exported under a Letter of Undertaking, but for a domestic SMB paying a domestic vendor, 18% GST on top of the maintenance fee should simply be built into the annual number you set aside.
A practical checklist before you sign
Before agreeing a development contract, it is worth asking the vendor to answer these directly:
- What is included in the maintenance retainer, and what counts as a chargeable change request on top of it?
- Is hosting billed separately from the maintenance fee, and who holds the cloud account?
- Who is responsible for renewing the Apple and Google developer accounts, and is that cost included or passed through?
- What response times apply for critical bugs versus minor issues?
- Is the first year of maintenance included in the build quote, or does it start as a separate line from month one?
- Does the maintenance fee scale if usage or data volume grows significantly?
Getting these answers in writing, ideally as part of the contract rather than a verbal assurance, avoids the common surprise of a renewal invoice that looks nothing like what was budgeted at kickoff.
Conclusion
A software or app budget that stops at the launch date is only half a budget. Setting aside 15–25% of the build cost annually for maintenance, accounting for small recurring platform fees, and clarifying GST and contract terms upfront turns an unpredictable future expense into a planned one. If you are scoping a new project and want help working through what a realistic first-year and ongoing budget looks like for your specific case, devtechnician is one option for Chennai-based businesses to get that conversation started.
