E-commerce replatforming without losing your search rankings

Moving an online store to a new platform is one of the highest-value projects a retailer can run — and one of the most dangerous for search traffic. Years of rankings are attached to URLs, content, and technical signals that a migration can silently destroy. The traffic drop appears weeks later, when it is expensive to reverse. It is entirely avoidable, but only if SEO is treated as a workstream of the migration rather than a check at the end.

This is the plan we run.

Before anything moves: inventory what ranks

Export every URL the search engines know about — from analytics, the search console, and a crawl of the current site — with its traffic and rankings. This inventory is the contract the migration must honour. Pages that earn traffic must survive with their equity intact; pages that earn nothing can be consolidated or dropped deliberately.

URL mapping and redirects

Every old URL needs a destination on the new platform: the same page, or the closest equivalent. Map them in a spreadsheet, review the mapping with someone who knows the catalogue, and implement permanent (301) redirects for every change. Redirect to the most relevant page, never to the home page in bulk. Chains — old URL to intermediate URL to final URL — leak equity and should be collapsed to a single hop.

Content parity

Product descriptions, category copy, titles, meta descriptions, image alt text, and internal links must arrive on the new platform intact. Migrations routinely truncate descriptions, lose alt text, or regenerate titles from templates. Compare a sample of important pages field by field before launch.

Structured data and technical signals

Product, breadcrumb, and organisation markup should exist on the new site and validate cleanly. Canonical tags must point to the right URLs, pagination must be handled consistently, and the sitemap must list the new URLs and nothing else. Check that the robots directives on the new platform do not accidentally block what the old one allowed.

Performance

Search engines reward fast pages, and a new platform is an opportunity to be faster — or a way to become slower. Measure page speed on the old site, set a target for the new one, and test on mobile before launch. Image weight and unused scripts are the usual culprits.

Staged cutover

Do not switch everything at once. Launch the new platform on a staging domain blocked from indexing, run the full checklist there, then cut over with redirects live from the first minute. If the catalogue is large, consider migrating sections in sequence so problems surface in one area rather than everywhere.

Monitoring after launch

Submit the new sitemap, then watch crawl errors, indexing coverage, and rankings daily for the first weeks. Redirect errors and missing pages show up here first. Keep the old URL inventory to hand: any URL that returns an error after launch is a ranking being lost in real time.

The mistakes we see most

Redirecting everything to the home page. Changing URL structure and content in the same move without necessity. Launching with the staging site's noindex tag still in place. Losing image alt text. Treating the migration as a design project with SEO "to be checked later." Each of these has cost retailers months of traffic, and each is preventable with the checklist above.

When the platform change is also a redesign

Replatforming and redesigning at once is common and doubles the risk, because content and structure change together. If you must do both, keep URL structure stable where possible, change content deliberately rather than by template, and give the SEO workstream a veto over launch. Our e-commerce development engagements are scoped this way; the migration plan is part of the written proposal, not an afterthought — a principle that applies across our retail and e-commerce work.

Frequently asked questions

Will we lose some traffic anyway? A small, temporary fluctuation is normal as search engines process the redirects. A sustained drop is a sign that something in the checklist was missed, and it is usually recoverable if caught early.

How long should we keep the redirects? Indefinitely. Old URLs live in bookmarks, emails, and external links for years.

Can we change our domain at the same time? You can, but it adds another layer of risk. If a domain change is necessary, plan it as its own step with its own monitoring.

Planning a move? Send us the platform you are leaving and the one you are considering, and we will outline the migration workstream with the SEO plan built in.