How Much Does Software Maintenance Cost Per Year? What's Included?

Many business owners, after happily "signing off" on their new software, are stunned to realize the invoices haven't stopped. Every year, they still pay a fixed amount just to keep the system running smoothly.

The truth is that this money is not a "hidden fee" or a vendor's trick. It's the inevitable operating cost of any living technology system. This article helps you understand the real numbers, what your money actually pays for, and why this is an investment you cannot cut.

How much is annual software maintenance?

An unwritten rule in the tech industry: annual software maintenance typically ranges from 15–20% of the original development contract value. For a system that cost VND 1B to build, the following year's maintenance budget lands around VND 150M–200M. This ratio is a common industry standard, applying to web apps, mobile apps, and ERP systems alike.

The 15–20% figure isn't absolute — it depends on system complexity, the number of third-party integrations (payments, shipping, accounting), and how often the business changes its processes. A small internal app with few external connections may only cost 15%. But if your system is large, plugged into many integration points (VNPay/Momo payments, GHTK shipping partners, MISA accounting software) and constantly getting new features, the number creeps toward 20%.

Estimated maintenance budget by project scale (VND):

Software scale	Build cost	Maintenance/year (15–20%)
MVP/small app	From 208M	~31M–42M
Mid-range	1.0B–3.1B	~150M–620M
Large scale	3.1B–6.2B+	~465M–1.24B+
ERP Starter (3–5 modules)	From 880M	~132M–176M
ERP Standard	1.4B–3.2B	~210M–640M
ERP Enterprise	3.2B–5B+	~480M–1B+

Reference prices; an exact quote follows a business analysis.

What items does software maintenance cover?

Don't think of maintenance as merely "call for a fix when it breaks." Software is a living entity, continuously affected by the network environment, users, and partners. Your maintenance package actually pays for these 5 essential categories of work:

Fixing bugs that surface during use

No software is 100% perfect at launch. A frozen button, a formula that miscalculates under heavy data, or an app that hangs — the IT team receives the bug report, triages severity, and resolves it per the agreed time commitment (SLA).

Security patching

This is the most easily forgotten yet most important item. Hackers find new vulnerabilities every day. If the system isn't patched in time, the business could face a customer-data breach disaster or ransom demands. Security patches require thorough testing before going to production, to avoid breaking features already running.

Upgrading libraries and platforms

Programming languages and servers always have an expiry date (End-of-Life). When an old platform is retired, your software must upgrade to a newer version to keep receiving support. This requires engineers to retest the entire system to ensure the old code still runs well on the new platform.

Adjusting for business and legal changes

Did your company change its order-approval process, or did the government issue a new tax law (such as a VAT change or e-invoicing standard)? Software doesn't automatically know this; the maintenance team is who rewrites the logic so the system keeps up with the new rules of the game.

Technical support and operations monitoring

Monitoring servers to prevent crashes during big sale days, handling connection outages with payment gateways, and answering 1-on-1 questions from your staff during use.

Why is software maintenance mandatory, not optional?

Software without maintenance is like driving a car that never gets an oil change. It still rolls for a few months, but once it breaks it burns out the whole engine — and the repair then costs dozens of times more than the maintenance would have. Cutting maintenance fees doesn't save you money; it merely defers that debt at a brutal interest rate, showing up as 3 risks:

Security risk accumulates over time. Every month that passes without patching vulnerabilities is another month the system's attack surface widens. A successful attack can cause damage many times an entire year's maintenance cost — from lost customer data and operational disruption to emergency remediation costs and reputational harm.

Technical debt piles up. Without regular updates, the gap between the running version and the platform's latest version grows ever wider. When you're finally forced to upgrade — because the old platform stops being supported — the cost and risk of a one-time leap across many versions is far higher than steady, incremental updates.

Business needs don't stand still. If the software can't keep pace with changes in pricing policy, operating processes, or legal regulations, it gradually becomes an obsolete tool — staff have to do manually what the software should handle, or worse, the system produces reports/invoices that violate regulations.

For these reasons, when budgeting a custom software project, maintenance cost must be counted from the start as part of the total cost of ownership (TCO), alongside the initial development cost — not as an unexpected charge later on.

How can businesses optimize maintenance costs?

Maintenance cost can be better controlled — not by cutting scope, but by choosing the right engagement model and technical architecture from the build phase. A well-designed, well-documented system using common technology will have far lower maintenance costs than one written hastily and dependent on rare, poorly-supported technology.

A few factors directly affect future maintenance cost:

• Initial code quality: a system written to standards, with automated tests (unit tests) and clear technical documentation, lets the maintenance team (even a different team from the builders) get up to speed quickly and fix bugs more accurately.
• Modular architecture: decoupling components means that fixing or upgrading one part doesn't cascade across the whole system.
• Contract model: with a Dedicated Team contract or a clear monthly maintenance SLA, the business knows its fixed budget exactly, instead of reacting to each incident. Choosing the right pricing model from the outset — see more in the article on Fixed Price, Time & Material, or Dedicated Team — also indirectly affects long-term operating costs.
• Transparent maintenance reporting: require the vendor to provide a detailed report of work done each period (bugs fixed, patches applied, resolution times) so the fee matches actual work, not an imposed number.

A business that owns 100% of its source code and data also gains options: it can run maintenance in-house, switch vendors, or renegotiate scope without being locked into a single provider.

Frequently Asked Questions

Is the maintenance fee negotiable? Yes. The 15–20% mark is the general baseline, but you can absolutely negotiate based on real needs (e.g., a lower fee if you only need business-hours support, not 24/7 coverage).

If I flatly refuse to pay maintenance, will the software "die" immediately? It won't die immediately, but it will "die slowly." Small bugs no one fixes become big ones, security gets riddled with holes, and data drifts further from business reality until the system is fully paralyzed.

What's the difference between warranty and maintenance? Warranty is like buying a new phone: free for the first few months to fix defects caused by the makers themselves. Maintenance is a long-term (paid) care service — including upgrades, defense against hackers, and expanding features over time.

Does a longer development time mean higher maintenance costs? Not directly, but they're related. A longer project implies more complex business logic and more extensive features. And the bigger the "house," the higher the cleaning and security (maintenance) costs naturally are, compared with a small one.

Software maintenance is part of the Total Cost of Ownership (TCO), not a "deal-with-it-later" fee. If you're budgeting to build a new app, or feel your current maintenance fee is unreasonable, contact a FutureTech expert (ftech.ltd). We're ready to audit your system and provide a transparent cost breakdown down to each line of code.

Reference prices; an exact quote follows a business analysis.