Website maintenance (TMA) contract cost for a B2B site in Amsterdam (2026)

The verdict in three sentences

A managed maintenance (TMA) contract costs between 150 and 800 EUR/month in Amsterdam in 2026, depending on the SLA level, included hours and the site's business criticality. It is insurance, not a luxury: an unmaintained B2B site accumulates vulnerabilities, outdated plugins and hacking risks whose average cleanup exceeds 8,000 EUR. The real question is not *what does maintenance cost*, but *what does its absence cost the day the site goes down*.

What a maintenance plan actually covers

A serious maintenance plan is not just "keeping the site online". It combines security, backups, monitoring and a pool of hours for minor evolutions. Here are the three tiers we see across the Amsterdam market in 2026.

Beyond the included hours, evolutions are billed on a time-and-materials basis at a day rate of 500 to 700 EUR. A 2h/month cap suits a stable brochure site; a B2B site with a client portal, CRM-connected forms and frequent updates justifies the Business or Critical tier.

Monthly retainer or time-and-materials

A monthly retainer smooths the budget and guarantees a contractual response time. Pure time-and-materials (pay per hour used) looks cheaper on paper but exposes you to provider unavailability and unpredictable delays.

The math is simple: two incidents avoided per year more than pay for an annual retainer.

Mini case study

Sarah, digital lead at an industrial SME in Amsterdam (45 staff), had a brochure site + reseller portal delivered in 2024 with no maintenance. In January 2026, an outdated form plugin was exploited: spam injection, sender IP blacklisted, site down for 3 days. Recovery invoice: 7,200 EUR, plus an estimated 12 lost leads over the period. She now pays a Business plan at 420 EUR/month (5,040 EUR/year). The single incident avoided since has already covered 18 months of subscription.

FAQ

Is maintenance mandatory after delivery?

Nothing legally requires it, but an un-updated CMS becomes vulnerable within months. In 2026, over 90% of SME site hacks exploit a known flaw already fixed by an update that was never applied.

Can I pay hourly instead of a retainer?

Yes, at a day rate of 500 to 700 EUR, but without a guaranteed response time or automated backups. For a lead-generating site, the retainer is safer.

What happens if I exceed the included hours?

Extra hours are billed at the contract rate (450 to 650 EUR/day). A good provider warns you before the overage and sends a quote first.

Is uptime monitoring really worth it?

Yes: without supervision an outage can last hours before anyone notices. The Business tier detects incidents in under 5 minutes and triggers an automatic alert.

What does a hacked site actually cost?

Between cleanup, backup restoration, security audit and lost business, the 2026 range is 3,000 to 8,000 EUR for an SME, not counting reputational damage.

Let's scope your project. Tell us about your site (CMS, criticality, traffic volume) and we will propose a maintenance plan calibrated between Essential and Critical, indicative budget 150 to 800 EUR/month. Detailed quote within 48 h. WhatsApp +221 77 596 93 33.