The verdict in three sentences
For a 25-person services SME in Berlin, the right entry point is a maintenance retainer of 300 to 500 EUR per month including 2 hours of changes and a 4 business-hour SLA. The basic plan at 150 to 250 EUR is enough if the site does not generate leads, but it covers neither functional fixes nor emergencies. Beyond 20 quote requests per month through the site, the 700 to 900 EUR plan with SEO and monthly reports usually pays for itself in under a quarter.
What a Next.js site costs without maintenance
A Next.js site is not a frozen static site: it depends on Node.js, dozens of npm packages, a host (Vercel, Hetzner, OVH, AWS Frankfurt) and often a headless CMS. Next.js ships a major version roughly every 12 months and security patches several times per quarter. Without follow-up, a site delivered in 2024 is two major versions behind in 2026, and the upgrade becomes a 3 to 6 day project.
| Typical incident without a contract | Estimated frequency per year | One-off fix cost (net) |
|---|---|---|
| Critical vulnerability in an npm dependency | 2 to 4 | 500 to 1,100 EUR |
| Broken contact form (mail API, captcha) | 1 to 2 | 400 to 900 EUR |
| Expired SSL certificate or DNS | 0 to 1 | 250 to 600 EUR |
| Next.js upgrade forced by the host | 1 | 2,250 to 5,700 EUR |
| Site down for more than 24 h | 0 to 1 | 1,500 to 3,000 EUR (excluding lost revenue) |
| Content loss without backup | rare | 2,500 to 6,000 EUR |
The average cost of an uncovered outage sits around 1,500 to 3,000 EUR once emergency handling, diagnosis and redeployment are billed at the premium hourly rate. In Berlin, senior freelancers and agencies charge 750 to 950 EUR per day, often +50% for emergencies. A single outage per year is enough to exceed the annual cost of an entry-level retainer.
The three retainer levels in Berlin in 2026
| Criterion | Essential | Standard | Growth |
|---|---|---|---|
| Monthly price (2026 ballpark, net) | 150 to 250 EUR | 300 to 500 EUR | 700 to 900 EUR |
| Next.js and dependency updates | monthly | monthly + patches within 72 h | weekly |
| Backups | daily, 30 days | daily, 90 days | daily + restore test |
| Uptime monitoring | every 5 min | every minute | every minute + SMS alerts |
| Included change hours | 0 | 2 h per month | 5 to 8 h per month |
| Blocking incident SLA | best effort | 4 business hours | 2 business hours |
| SEO and monthly report | no | technical report | SEO audit, content, Core Web Vitals |
Three points deserve a check in the contract. First, rollover of unused hours: some providers drop them at month end, others pool them over a quarter. Second, the definition of a blocking incident: quote form unreachable, site offline, failed payment. Third, reversibility: access to the Git repository, hosting accounts and domain names held in the SME's name, never the agency's. Under GDPR, also confirm the provider signs a data processing agreement (Art. 28) if it accesses form data.
How to size the retainer to the site's use
The right level depends on what the site earns, not its size. A 10-page site generating 30 quote requests a month deserves more care than a purely corporate 40-page site.
| Site profile | Monthly leads | Recommended plan | Annual budget (net) |
|---|---|---|---|
| Corporate brochure site | under 5 | Essential | 1,800 to 3,000 EUR |
| Services site with form | 5 to 20 | Standard | 3,600 to 6,000 EUR |
| Services site with booking | 20 to 60 | Standard or Growth | 6,000 to 10,800 EUR |
| Multi-office site with active blog | over 60 | Growth | 8,400 to 10,800 EUR |
| Site with customer portal | variable | Growth + support contract | 15,000 EUR and up |
Mini case study
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Jonas, managing director of a 25-person IT services SME in Berlin, received his Next.js site in 2024 without a contract. In 2025, two incidents: quote form broken for 9 days after a mail API change (fix 800 EUR), then a host-imposed version upgrade (3,000 EUR). Total: 3,800 EUR, not counting lost leads. The site generated 18 requests per month with a 15% conversion rate and an average deal of 4,000 EUR: 9 days of downtime means about 5 lost requests, close to 3,000 EUR of potential margin. With a Standard retainer at 390 EUR per month, or 4,680 EUR per year, Jonas would have had patches included, 24 hours of changes over the year and outage detection in under an hour.
FAQ
What is the minimum price for serious maintenance of a Next.js site?
Count on 150 to 250 EUR per month in Berlin for updates, backups and monitoring. Below 150 EUR, the provider cannot test updates before deployment, which raises the regression risk.
Does the retainer cover new pages?
Only within the included hours, usually 2 h per month on the Standard plan. A full service page takes 3 to 5 hours, so hours pooled over a quarter are often more useful.
What does a 4 business-hour SLA mean?
The provider commits to picking up a blocking incident within 4 business hours of the report, for example 9 am to 6 pm Monday to Friday. Full resolution time is separate and must be specified, often 1 business day.
Can we switch maintenance provider easily?
Yes, if the Git repository, hosting and domain name are in your name. Plan half a day to a full day of handover, about 400 to 950 EUR, for audit and documentation.
Is a 12-month commitment required?
Most Berlin retainers are annual with a 10 to 15% discount versus monthly with no commitment. A notice period of 1 to 3 months is standard.
Let's scope your project. We audit your Next.js site and propose a maintenance retainer matched to your lead volume, from 150 to 900 EUR per month, live within 10 days. 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.
