The verdict in three sentences
A successful 2026 migration is judged not on design but on preserving organic traffic and revenue. Drops almost always come from missing 301 redirects, broken URLs and rushed QA before go-live. With a rigorous plan, you target less than 5% revenue loss over the 6-to-10-week risk window.
Migration cost by catalog size
Cost depends mainly on SKU volume, integrations and the depth of data to carry over (accounts, orders, reviews).
| Catalog size | SKUs | Indicative 2026 cost | Timeline |
|---|---|---|---|
| Small | 500-2,000 | 8,000-15,000 EUR | 4-6 weeks |
| Medium | 2,000-10,000 | 15,000-25,000 EUR | 6-9 weeks |
| Large | 10,000-30,000 | 25,000-35,000 EUR | 8-12 weeks |
| Very large | 30,000-50,000 | 35,000-40,000 EUR | 10-14 weeks |
Add 20-30% if you carry over full order and customer-account history including credit terms.
Causes of loss and how to neutralize them
Every point of loss has an identifiable cause and a fix. Pre-launch QA is where revenue is secured.
| Cause of drop | Typical impact | Fix |
|---|---|---|
| Missing 301s | -20 to -40% traffic | exhaustive URL mapping |
| Lost SEO tags | -10 to -25% | export/reimport meta |
| Degraded speed | -5 to -15% conversion | Core Web Vitals > 90 |
| Accounts not migrated | abandonment spikes | migration + password reset |
| Broken product feeds | marketplace delisting | feeds revalidated pre-switch |
| Broken tracking | flying blind | GA4/consent tested in staging |
Need a professional website?
Kolonell builds websites that attract clients, optimized for the Sénégalese market. Free quote in 2 minutes.
Mini case study
Sophie, e-commerce director of a supplies distributor in Bordeaux, is migrating 8,500 SKUs. Her monthly online revenue is 220,000 EUR. With no redirect plan, a 25% organic traffic loss would cost her about 55,000 EUR in the first month. By investing 4,500 EUR more in exhaustive 301 mapping and SEO QA, she holds the loss to 4%, i.e. 8,800 EUR: the QA plan paid for itself more than fivefold in the first week.
FAQ
How long is the risk window? Expect 6 to 10 weeks after the switch, the time Google needs to recrawl and reindex. Monitor traffic, rankings and revenue daily during this period.
Are 301 redirects really critical? Yes. A single mis-redirected category can cost 10 to 20% of organic traffic. Exhaustive URL mapping is the highest-ROI task of any migration.
Should we migrate order history? For a B2B with credit terms and reorders, yes: it is essential to loyalty. It adds 20-30% to the budget but avoids service disruptions for pro customers.
What revenue-loss target should we aim for? A well-run project stays under 5% loss over the risk window, returning to prior levels in 6-8 weeks. Beyond 10%, QA was insufficient.
Can we migrate with no downtime? Yes, via a scheduled DNS switch outside peak traffic and a 100%-validated staging environment. Plan a rollback executable in under 30 minutes.
Let's scope your project. Tell us your current platform, SKU count and online revenue, and we will price the migration and QA plan to stay under 5% loss. 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.
