The verdict in three sentences
If your site is under 5 years old, with recoverable Core Web Vitals and SEO that earns, a redesign (8,000-18,000 EUR) preserves your equity at lower cost. If the code is over 6 years old, if technical debt exceeds 40% of a redesign's cost, or if the structure blocks you, a new site (12,000-30,000 EUR) costs more but avoids paying twice. The central criterion isn't aesthetics but the technical debt and the SEO you risk losing.
The 40% rule: redesign or rebuild
Assess the cost of bringing the existing site up to standard versus a full rebuild.
| Criterion | Favours redesign | Favours new site |
|---|---|---|
| Code age | < 5 years | > 6 years |
| Estimated technical debt | < 40% of redesign cost | > 40% of redesign cost |
| Current Core Web Vitals | Recoverable (LCP < 4s) | Unrecoverable without rebuild |
| SEO equity | Strong, to preserve | Weak or to rebuild |
| Structure / CMS | Healthy, extensible | Obsolete, blocking |
| Brand design | To refresh | To rethink entirely |
If three or more criteria lean right, rebuilding is more cost-effective than patching.
Cost, timeline and SEO: the 2026 figures
In Dublin, 2026 orders of magnitude for a B2B site of 15-25 pages.
| Line item | Redesign | New site |
|---|---|---|
| Upfront cost | 8,000-18,000 EUR | 12,000-30,000 EUR |
| Delivery time | 6 weeks | 10 weeks |
| SEO loss risk | Low (URLs kept) | Medium (redirects to manage) |
| Editorial cost (content migration) | 1,000-3,000 EUR | 3,000-6,000 EUR |
| Expected performance gain | +20 to 40% | +40 to 70% |
| Estimated lifespan | 3-4 years | 5-7 years |
The new site costs more but lasts longer: on a per-year basis, the TCO gap narrows sharply.
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Mini case study
Nadia is managing director of a trading SME in Dublin, a 2018 site on an ageing CMS, LCP at 5.2s and 1,200 SEO visitors/month. One provider proposes a redesign at 14,000 EUR; another a new site at 24,000 EUR. An audit reveals that upgrading the CMS and technical debt alone costs about 7,000 EUR, i.e. 50% of the redesign cost, beyond the 40% threshold. With a redesign she'd likely pay for a rebuild again in 3 years. Nadia picks the new site: 10,000 EUR more upfront, but a 6-year lifespan instead of 3, i.e. an annualised cost of 4,000 EUR versus 4,700 EUR for the redesign. She preserves her SEO via a thorough 301 redirect plan. Verdict: past the 40% threshold, rebuilding costs less per year.
FAQ
How do I know if my technical debt exceeds 40%? Ask for an audit costing the code, CMS and performance upgrade. If that figure exceeds 40% of the redesign quote (i.e. ~5,600 EUR on a 14,000 EUR redesign), rebuild.
Will I lose my SEO by rebuilding my site? Not if you keep the URLs (redesign) or implement complete 301 redirects (new site). A botched migration can cost 20-40% of traffic over 3-6 months.
How long does each option take? Expect around 6 weeks for a redesign and 10 weeks for a new site, scoping, content and approvals included.
Is a redesign always cheaper long term? No: a redesign at 8-18k EUR lasting 3 years can cost more per year than a new site at 12-30k EUR lasting 6 years. Think in annualised cost.
What budget should I plan in Dublin in 2026? 8,000-18,000 EUR for a redesign, 12,000-30,000 EUR for a new site, plus 1,000-6,000 EUR of content migration.
Let's scope your project. Send us your current site URL and your goals; we'll audit the technical debt and tell you whether a redesign (8-18k) or a new site (12-30k EUR) is the right bet. 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.
