The verdict in three sentences
For a consultancy in Amsterdam, a WordPress maintenance retainer costs between 1,800 and 7,200 EUR per year in 2026 depending on the service level. The entry plan at 150 to 250 EUR per month prevents most hacks, which exploit outdated plugins. Once the site drives meeting requests or publishes thought leadership every month, a 400 to 600 EUR plan with development hours, a 4-hour fix SLA and service credits is the most cost-effective choice.
What a maintenance retainer actually covers in 2026
A consultancy WordPress site typically runs 15 to 25 plugins: page builder, forms, SEO, caching, cookie consent, multilingual, booking. Each ships security updates several times a year. The 2025 hacks we see most often follow the same pattern: a form plugin left outdated for six months, an injected script, redirects to spam sites, then a Google ranking drop within days.
| Plan | Monthly price 2026 (ex. VAT) | Scope | Response time |
|---|---|---|---|
| Essential | 150 to 250 EUR | Core and plugin updates, daily backups, monthly report | 2 business days |
| Secure | 250 to 400 EUR | Essential + 24/7 monitoring, web application firewall, quarterly restore test | 1 business day |
| Business | 400 to 600 EUR | Secure + 3 dev hours/month, fixes within 4 h, performance tuning | 4 business hours |
| Enterprise | 700 to 1,200 EUR | Business + 8 dev hours, on-call, biannual security audit | 2 h, 7 days a week |
| Ad hoc, no contract | 95 to 140 EUR/h | One-off work, no monitoring | Best effort |
| Post-hack cleanup | 1,500 to 4,500 EUR | Cleanup, restore, hardening, spam de-indexing | 2 to 5 days |
The last row matters most to an office manager: one incident costs as much as 10 to 18 months of the Essential plan, before counting lost leads during downtime.
SLA and penalties: the clauses that separate offers
Two quotes at 400 EUR per month can cover very different realities. Dutch agencies increasingly attach a formal SLA with service credits. Ask for these points in writing.
| Clause | Weak offer | Strong offer | Impact for the firm |
|---|---|---|---|
| Uptime target | None | 99.9 % monthly, measured by external monitor | About 43 min of downtime allowed per month |
| Service credit | None | 10 % of monthly fee per 0.1 % below target, capped at 50 % | Real incentive to fix fast |
| Critical fix time | "As soon as possible" | 4 business hours, 1 h acknowledgement | Enforceable commitment |
| Backups | Weekly, same server | Daily, off-site, 30-day retention | Restore even if host fails |
| Updates | Auto, untested | Tested on staging first | No broken site on Monday morning |
| Dev hours | Not included | 3 h/month, rolls over 1 month | New pages without a quote |
| Exit clause | Agency keeps access | Admin, hosting and DNS in the firm's name | Switch providers freely |
Under GDPR, the contract should also include a data processing agreement, since the agency accesses form submissions. For a 20 to 40 page site, a good provider spends 1.5 to 2.5 hours per month on maintenance alone.
Mini case study
Sophie, office manager at a 14-consultant strategy firm in Amsterdam, saw the site hacked in March 2025. Cleanup invoice: 2,800 EUR, plus about 6 days without a working contact form. The firm receives around 9 qualified leads per month via the site, signs 20 % of them, with an average engagement of 15,000 EUR.
One-year calculation:
- Business plan at 480 EUR per month: 5,760 EUR per year, including 36 dev hours (around 4,000 EUR of ad hoc time at 110 EUR/h).
- Avoided incident: 2,800 EUR cleanup + 2 lost leads, so 0.4 likely engagement, roughly 6,000 EUR of gross margin.
- The retainer pays for itself with a single avoided incident, and the dev hours replace one-off quotes the firm was already paying.
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Sophie signed a 450 EUR plan with a 99.9 % uptime SLA, 10 % service credits and admin access returned to the firm.
FAQ
How much does WordPress maintenance cost for a consultancy in Amsterdam in 2026?
Expect 150 to 250 EUR per month for updates and backups, and 400 to 600 EUR per month with dev hours and a 4-hour fix SLA. Over a year, budget 1,800 to 7,200 EUR depending on the level.
Are WordPress auto-updates enough?
It is risky: on a site with 15 to 25 plugins, roughly one automatic update in two hundred breaks a layout or a form. A provider tests updates on staging first, which avoids most incidents.
What does a service credit look like in practice?
A typical clause refunds 10 % of the monthly fee for every 0.1 % of uptime below a 99.9 % target, capped at 50 %. It is modest in euros but forces the agency to monitor and react quickly.
Should we sign for 12 months?
Most providers offer 12-month terms at 10 to 15 % less than month-to-month. Check the exit clause first: all access must stay in the firm's name.
What happens if the site gets hacked despite the retainer?
A serious contract includes cleanup from the Business level up, with a 4-hour response. Without one, the bill ranges from 1,500 to 4,500 EUR plus time to de-index spam pages.
Let's scope your project. Send us your site URL and plugin list and we will price a maintenance retainer from 150 to 600 EUR per month with an SLA, including a baseline audit within 5 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.
