Website Maintenance Retainer Cost for B2B (2026)

The verdict in three sentences

A maintenance retainer for a B2B website ranges in 2026 from EUR 90 to 1,500 per month depending on updates, monitoring and the guaranteed SLA. The basic tier protects (backups, security patches), the standard tier evolves (4 hrs/month included), the premium tier commits to a contractual recovery time. Skipping maintenance costs more than any retainer: one exploited CMS vulnerability means, on average, 3 to 8 days of downtime plus a rebuild billed as a project.

What a maintenance retainer really covers

Maintenance is more than updates. A serious contract covers four blocks: corrective (bugs, vulnerabilities), preventive (backups, monitoring, CMS/plugin updates), evolutive (small monthly improvements) and support (guaranteed response time). The classic trap: a EUR 90/month deal covering only corrective work, with no development hours or SLA. You think you are covered; you are only covered on paper.

2026 pricing benchmarks by tier

The ranges below are a 2026 order of magnitude for a B2B brochure or corporate site hosted in the EU. Prices rise with the number of sites, business criticality and availability requirements.

Mini case study

Thomas, IT director of a 120-employee industrial SME in Nantes, runs a corporate site plus a catalogue portal. Without a contract he pays hourly: about 6 hrs/month at EUR 100, i.e. EUR 600, plus an emergency rebuild after a hack last year billed at EUR 4,200. Moving to a standard retainer at EUR 420/month (EUR 5,040/year) with 4 included dev hours and monitoring smooths the cost, prevents the major incident and gives him a monthly report to justify the budget in committee. Estimated saving over 24 months, security incident avoided: around EUR 5,000.

FAQ

How much does WordPress maintenance cost in 2026? Expect EUR 90-150/month for a basic tier (backups + updates) and EUR 250-500/month for a standard tier with 4 dev hours and monitoring. A critical site with an SLA exceeds EUR 800/month.

What is an SLA on a maintenance contract? The SLA (service level agreement) sets a guaranteed recovery time: 8 business hours on standard, 4 hours on premium. Below that, there is no commitment and your outage can last several days.

Is maintenance mandatory? Not legally, but an outdated CMS is the number-one cause of hacking. An unpatched vulnerability causes on average 3 to 8 days of downtime and a rebuild billed at EUR 3,000-6,000.

Can unused development hours roll over? Depending on the contract, the 4 hrs/month can sometimes accumulate over a quarter. Check this clause: without rollover, you lose the unused quota each month.

Do I need a contract for a simple brochure site? Yes, at least a basic tier at EUR 90-150/month: daily backups and security patches cost far less than rebuilding a hacked site.

Let's scope your project. Tell us about your site fleet, your CMS and your availability needs, and we will size a maintenance retainer (basic, standard or premium with SLA) at the right cost. Detailed quote within 48 h. WhatsApp +221 77 596 93 33.