The verdict in three sentences
If your CMS is under five years old, your PageSpeed score clears 50 and technical debt stays below 30% of dev time, a redesign at 3,000-6,000 EUR is enough. Past those thresholds, every euro poured into the old base is wasted: commit to a full rebuild at 8,000-18,000 EUR. The real cost is not the project but the status quo: -20% conversion and +2s load time quietly erode your revenue every month.
The four signals that settle it
A decision maker does not choose on gut feel; they read numbers. Here is the 2026 decision grid separating a simple redesign from a heavy rebuild.
| 2026 signal | Redesign is enough | Rebuild required |
|---|---|---|
| CMS age | < 5 years | > 5 years or end of support |
| Mobile PageSpeed | > 50 | < 50 |
| Technical debt (% dev time) | < 30% | > 30% |
| Conversion vs 2023 | stable | -20% or worse |
| Mobile compatibility | responsive OK | broken on mobile |
| Monthly maintenance cost | < 300 EUR | > 600 EUR |
As soon as three rows flip right, the rebuild becomes the cheaper option over three years. Patching an obsolete base is like repainting a house with a cracked frame.
What each path actually costs
The sticker price hides the total price. Compare both trajectories over 24 months for a B2B corporate site in New York.
| Line item (2026) | Redesign | Full rebuild |
|---|---|---|
| Upfront cost | 3,000-6,000 EUR | 8,000-18,000 EUR |
| Delivery time | 2-4 weeks | 6-10 weeks |
| Speed gain | +15 to 25% | +50 to 70% |
| Estimated lifespan | 2-3 years | 5-6 years |
| Annual maintenance | 1,200-2,400 EUR | 1,800-3,600 EUR |
| Rework risk at 18 months | high | low |
A redesign postpones the problem; a rebuild removes it. If you know your base will not last three years, paying twice (redesign then rebuild) costs more than a single well-scoped rebuild.
Mini case study
Philip runs a 40-employee industrial SME in New York. His site, on a 2018 CMS, scores 38 on mobile PageSpeed and has lost 22% of quote requests in two years. Redesign quote: 5,000 EUR. But the audit reveals technical debt at 45% of dev time. He picks the rebuild at 12,000 EUR. Twelve-month result: load time drops from 4.1s to 1.3s, conversion up 34%, meaning 18 extra quote requests per month. At an average deal of 4,000 EUR, the investment pays back in under four months.
Need a professional website?
Kolonell builds websites that attract clients, optimized for the Sénégalese market. Free quote in 2 minutes.
FAQ
How much does a B2B site redesign cost in 2026?
Expect 3,000 to 6,000 EUR for a light visual and technical refresh, delivered in 2 to 4 weeks. Beyond that, you enter rebuild territory.
How do I know if my CMS is obsolete?
A CMS over five years old, past vendor support, or one whose updates break the site is obsolete. 40% of web breaches come from unmaintained bases.
What is the hidden cost of the status quo?
A slow site (+2s load) loses roughly 20% of conversions. On a site generating 50 requests/month, that is 10 leads lost every month.
Does a rebuild really improve SEO?
Yes, if it preserves URLs and redirects the old ones cleanly. A well-run rebuild gains 30 to 50% in speed, a direct ranking factor since 2021.
How long does a full rebuild take?
Between 6 and 10 weeks for a B2B corporate site, depending on page count and CRM integration. A redesign fits in 2 to 4 weeks.
Let's scope your project. Send us your URL and goals: we audit your PageSpeed, technical debt and conversion, then settle redesign or rebuild with a clear indicative budget. 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.
