The verdict in three sentences
A botched migration can drop organic traffic by 30 to 60% in weeks, but a well-run migration limits the transient loss to under 5%, recovered in 60 to 90 days. The heart of the matter is not the new design: it is the 301 redirect map and the preservation of strategic URLs. Budget 3,500 to 8,000 EUR for the migration/SEO scope and a 4-to-8-week risk window.
The 12-point checklist
This sequence separates a controlled migration from an industrial accident. Each step is ticked before moving to the next.
| # | Step | Timing | Tool |
|---|---|---|---|
| 1 | Full crawl of the old site | Before | Screaming Frog |
| 2 | Export URLs + traffic | Before | Search Console / GA4 |
| 3 | Identify strategic URLs | Before | Traffic/leads analysis |
| 4 | Map 301 redirects | Before | URL -> URL spreadsheet |
| 5 | Keep key URL structure | Before | Sitemap rule |
| 6 | Carry over title/meta tags | Before | CMS |
| 7 | Test 301s in staging | Cutover | Test crawl |
| 8 | Go-live + XML sitemap | Cutover | CMS / robots.txt |
| 9 | Submit to Search Console | Cutover | Search Console |
| 10 | Post-migration crawl | After | Screaming Frog |
| 11 | Monitor rankings/404s | 30 d | Search Console |
| 12 | Fix residual 404s/301s | 30-90 d | Server logs |
Budget and risk window
Cost depends on URL volume and mapping complexity. A 40-page brochure site is not a 4,000-URL site.
| URL volume | 301 mapping | 90-day monitoring | Total budget (EUR) |
|---|---|---|---|
| < 100 | 500 - 1,000 | 800 - 1,500 | 3,500 - 5,000 |
| 100 - 1,000 | 1,200 - 2,500 | 1,500 - 2,500 | 5,000 - 7,000 |
| 1,000 - 5,000 | 2,500 - 4,500 | 2,000 - 3,500 | 6,500 - 9,000 |
| > 5,000 | on quote | on quote | 8,000 - 15,000 |
Target outcome: transient traffic loss < 5%, return to prior level in 60 to 90 days, zero orphaned strategic page.
Mini case study
Sarah, COO of a trading firm in Amsterdam, migrates a 320-page site generating 45 leads/month. Without a plan, she would risk losing 15 to 25 leads/month during the dip. With the plan: pre/post crawl, 280 mapped 301 redirects, preservation of the 12 top-performing product pages. Migration budget: 6,200 EUR. Measured result: -4% traffic the first week, back to 100% in 7 weeks, zero leads lost over the quarter. A botched migration would have cost dozens of leads.
FAQ
Need a professional website?
Kolonell builds websites that attract clients, optimized for the Sénégalese market. Free quote in 2 minutes.
Will I necessarily lose traffic when migrating?
A transient 2-to-5% dip is normal while Google re-crawls. Well managed, it recovers in 60 to 90 days. A lasting drop signals a redirect problem.
Are 301 redirects enough?
They are the foundation, but not everything. You must also preserve tags, internal linking and strategic URLs, and monitor 404s after cutover.
How long should I keep the old redirects?
At least 12 months, ideally permanently. Removing them too early breaks authority transfer and creates 404s.
Can I change domain and redesign at the same time?
Possible but risky. If you can, separate the projects: domain change first, redesign second, to isolate the cause of any drop.
Which tool verifies my migration?
A crawler (Screaming Frog) for 301s and 404s, plus Search Console for indexing and rankings. Cross-referencing both detects 90% of issues.
Let's scope your project. Tell us your URL volume, current and target CMS and your cutover date: we price the migration plan and 90-day monitoring. 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.
