The verdict in three sentences
A web app is not a frozen deliverable: without application maintenance (AMS), it degrades within 12 to 18 months. In Toronto in 2026, budget 10 to 20 % of the build cost per year, i.e. around 6,000 to 24,000 USD/year for an app built at 60,000 USD, plus the infra run. Good maintenance covers fixes, enhancements, security and a written SLA, not just "we check if it breaks".
What application maintenance covers
Maintenance bundles everything that keeps the app alive, secure and aligned with the business after delivery. It differs from the run (infrastructure) and from major enhancement projects, billed separately.
| Item | Content | Frequency |
|---|---|---|
| Bug fixes | Blocking and minor defects | Ongoing |
| Security updates | Dependencies, CVEs, patches | Monthly |
| Small enhancements | Business tweaks, fields, screens | As needed |
| Monitoring & alerts | Uptime, errors, performance | 24/7 |
| Backups & restore | Tested backups | Daily |
| User support | Tickets, level 2 | Business hours |
2026 pricing grid
Maintenance price is most often calculated as a percentage of the build budget. The more critical and complex the app, the higher the percentage.
| Build cost | AMS 10 %/yr | AMS 15 %/yr | AMS 20 %/yr |
|---|---|---|---|
| 30,000 USD | 3,000 USD | 4,500 USD | 6,000 USD |
| 60,000 USD | 6,000 USD | 9,000 USD | 12,000 USD |
| 90,000 USD | 9,000 USD | 13,500 USD | 18,000 USD |
| 120,000 USD | 12,000 USD | 18,000 USD | 24,000 USD |
On top of that comes the infrastructure run: hosting, database, CDN, monitoring, between 300 and 900 USD/month depending on load and criticality.
| SLA level | Acknowledgement time | Indicative AMS cost |
|---|---|---|
| Basic | 24-48 business hours | 10-12 % of build/yr |
| Standard | 8-24 business hours | 13-16 % of build/yr |
| Enhanced | 4 business hours | 17-20 % of build/yr |
| Critical 24/7 | 1-4 h, on-call | quote-based, +20 % |
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Mini case study
Julien, CIO of a mid-sized manufacturer in Toronto, had a production-management app built for 80,000 USD. He hesitates to sign a maintenance contract. In the first year without maintenance, the app piles up 3 unpatched security flaws and 11 untreated bugs; one incident halts production for half a day, estimated cost 8,000 USD.
He finally signs a standard AMS at 15 %: 12,000 USD/year, plus 600 USD/month of run, i.e. 19,200 USD/year all-in. In exchange: a 12-hour SLA, monthly security patches and 3 enhancement days included per quarter. ROI is reached at the very first incident avoided, not counting the value of ongoing enhancements.
FAQ
Is maintenance mandatory? Not contractually, but without it an app degrades fast: security debt, incompatibilities, untreated bugs. It is insurance, not a luxury.
Can I do maintenance in-house? Yes if you have a spare dev team, but a developer's loaded cost (over 5,000 USD/month) often exceeds external maintenance for a single app.
What if I don't use my hours? Depending on the contract, they are lost (fixed fee) or carried over (capped T&M). Prefer a fixed fee with partial carry-over to smooth the load.
Is the run included in maintenance? Rarely. Hosting and infra (300-900 USD/month) are usually billed separately from the application maintenance fee.
How does this compare in Europe? French/European grids run around 8 to 18 % of build/year with lower day rates; the percentage order of magnitude stays comparable.
Let's scope your project. Tell us your app's build cost and its criticality: we propose a maintenance package with a fitting SLA and a separate run line. Detailed quote within 48 h. WhatsApp +221 77 596 93 33.
Mohamed Bah
Fondateur, Kolonell
Passionate about digital and entrepreneurship in Africa, Mohamed has been helping Sénégalese businesses with their digital transformation since 2020. Founder of Kolonell, he believes every SME deserves a professional and accessible online présence.
