Short answer: a common rule of thumb is to budget around 15–20% of the original development cost per year for software maintenance. For many business applications that means roughly $1,000–$5,000 per month, while small websites and simple apps cost less and large platforms with many integrations cost more. The right budget depends on the size, age and importance of your software.
Software maintenance cost at a glance
| Software | What maintenance includes | Approximate monthly cost* |
|---|---|---|
| Business website (e.g. WordPress) | Core, theme and plugin updates, backups, security, small changes | $100–$500 |
| Simple web or mobile app | Bug fixes, OS and library updates, monitoring | $500–$2,000 |
| Business application or portal | Updates, security patches, integrations, small enhancements | $1,000–$5,000 |
| Enterprise platform | Dedicated support, SLAs, performance work, frequent releases | $5,000+ |
*Approximate ranges for 2026. Your cost depends on scope, technology and response-time requirements.
The four types of software maintenance
| Type | What it means | Example |
|---|---|---|
| Corrective | Fixing bugs and errors | A checkout error on certain devices |
| Adaptive | Keeping software working as its environment changes | Updating for a new iOS version or upgrading from .NET 8 to .NET 10 |
| Perfective | Improving performance and usability | Faster pages, simpler forms, better reports |
| Preventive | Reducing future problems | Refactoring old code, adding tests, updating libraries |
What affects maintenance cost?
- Size and complexity: more features, users and integrations mean more to maintain.
- Age and technical debt: older code, outdated frameworks and missing tests increase effort.
- Technology support cycles: frameworks such as .NET, PHP and mobile operating systems retire versions regularly. Read about the .NET 8 end of support.
- Third-party dependencies: APIs and libraries change and need updating.
- Security and compliance: regulated industries need more frequent patching and audits.
- Response times: 24/7 support and short response times cost more.
- Hosting: cloud and server costs are usually separate from maintenance work.
What a maintenance plan should include
- Security updates and patching for frameworks, libraries and servers.
- Bug fixing with agreed priorities and response times.
- Framework and operating system upgrades.
- Uptime and error monitoring, plus tested backups.
- Performance checks and optimisation.
- A set number of hours for small improvements.
- A monthly report of work completed and recommendations.
Pricing models
| Model | How it works | Best for |
|---|---|---|
| Monthly retainer | A set number of hours each month | Most business applications |
| Dedicated support developer | A developer who knows your system works on it every month | Larger or business-critical systems |
| Pay as you go | Pay hourly for each request | Small websites with few changes |
| One-off audit or rescue | Fixed-price review and stabilisation | Software that has been neglected or inherited |
The cost of not maintaining software
- Security breaches through unpatched vulnerabilities.
- Apps breaking after iOS, Android or browser updates.
- Slow performance that drives customers away.
- Expensive emergency fixes and, eventually, a full rebuild.
- Failing security audits or customer due-diligence checks.
How to reduce maintenance cost
- Keep frameworks and libraries up to date in small steps instead of large, rare upgrades.
- Invest in automated tests and CI/CD.
- Document your system and infrastructure.
- Monitor errors and performance to catch issues early.
- Remove features and integrations nobody uses.
Get a maintenance plan from Three Circle
We maintain web applications, mobile apps and websites built on .NET, Node.js, PHP, React, Flutter and more, including software built by other teams. See our software maintenance and support services or request a free consultation.
Frequently asked questions
A common rule of thumb is 15–20% of the original development cost per year, depending on size, age and complexity.
Bug fixes, security updates, framework and OS upgrades, monitoring, backups, performance work and small improvements.
Usually not. Hosting, cloud services and licences are typically billed separately from maintenance work.
Yes. Most teams start with a code and infrastructure audit, then take over maintenance with a clear plan.
Security risks grow, updates break features and fixes become more expensive over time, often leading to a costly rebuild.
