Correct 301 redirects when replatforming are the single most important measure for keeping your organic traffic. Your store’s positions in the search results are tied to your URLs — every product page, category page and guide that has gathered links and trust over the years. When the platform changes and the addresses change with it, that link equity must move too. That is exactly what a 301 redirect does: it tells the search engines that the page has a new permanent address.
Skip that work and both Google and your visitors are met by 404 pages, and the positions you have built go to your competitors. This guide shows how to do the redirect work right: inventory, redirect map, testing and the mistakes that most often go wrong.
Why a 301 redirect when replatforming — and not a 302
There are two common ways to point a URL somewhere else, and the difference matters. A 301 says “the page has moved permanently” — the search engine transfers the page’s signals to the new address and replaces it in the index. A 302 says “the page is temporarily elsewhere” — the search engine keeps the old address and waits. In a platform switch the move is permanent, so every redirect should be a 301. It sounds obvious, but the wrong status code is one of the most common launch mistakes, often because the new platform’s default setting responds with a 302.
Step 1: Inventory all your URLs
You can’t redirect addresses you don’t know about. Build a complete list of the store’s URLs from several sources — no single source catches everything:
- A crawl of the site with a spidering tool — catches everything that is linked internally.
- Google Search Console — shows which pages actually get impressions and clicks.
- Your analytics tool — shows landing pages with traffic, including from campaigns and newsletters.
- The sitemap from your current platform.
- A backlink analysis — pages with external links are your most valuable addresses and absolutely must not be lost.
Merge the sources, remove duplicates and prioritise the list by traffic and link value. The pages at the top deserve manual handling; the long tail can be handled with rules.
Step 2: Build the redirect map — rules before individual rows
The redirect map is a table with two columns: old URL and new URL. But don’t try to write tens of thousands of rows by hand. Start with the patterns.
Most platforms have systematic URL structures. If the old store has addresses like /product/item-name and the new one uses /p/item-name, a single rule can handle the entire product catalogue. Work in this order:
- Write pattern rules for products, categories and content pages.
- Handle the exceptions manually: pages that change name, get merged or disappear.
- Decide targets for pages with no equivalent — the nearest category or a relevant guide, never the homepage by default.
- Document the decisions so that whoever maintains the site in two years understands the logic.
Don’t forget what isn’t HTML pages: image addresses that rank in image search, PDF files, feeds and old campaign URLs with parameters. And decide how filtered and paginated pages should be handled — they rarely need redirecting one by one, but they shouldn’t be left as thousands of 404 errors either.
Step 3: Test before launch — not after
The redirect map should be verified in a staging environment before DNS is switched. Run the full URL list from step 1 through staging and check three things for every address: that it responds with exactly a 301, that it lands on the right target page, and that it does so in a single hop. Chains — where an old URL points to an address that in turn points onwards — leak link equity and slow the site down. Always point directly to the final target.
The most common mistakes
- Everything points to the homepage. Search engines treat this in practice as if the pages were deleted, and the visitor who clicked a product link lands on a page that doesn’t help — a double loss.
- 302 instead of 301. The link equity doesn’t transfer. Check the status code, don’t assume it.
- The redirects are cleaned away too early. External links point to old addresses for many years. Let the redirects live on — they cost nothing.
- Internal links are forgotten. The new site should link directly to new URLs, not take the detour via redirects.
- No monitoring after launch. Follow the 404 reports in Search Console daily for the first weeks and fix the holes as you go.
Checklist for launch day
- The redirect map covers all URLs from the inventory, prioritised by traffic and link value.
- The whole map is tested in staging: right status code, right target, no chains.
- A new sitemap is ready to be submitted to Search Console immediately at launch.
- Internal links, feeds and ad destinations point to new URLs.
- Monitoring of 404 errors and indexing is in place from day one.
After launch: measure, fix, be patient
Even with a perfect redirect map, search results move after a platform switch. The search engines have to recrawl the site, evaluate the new pages and update their index — that takes time, and some movement in positions during the transition is normal. What you should react to is not movement but patterns: whole sections dropping, 404 errors growing instead of shrinking, or important pages not being indexed.
Set a simple routine for the first weeks: go through Search Console’s reports on indexing and 404 errors, compare organic landing pages against the state before the switch and fix the holes as you go. Every 404 you find is either a row missing from the map or an external link pointing wrong — both can be fixed the same day they are discovered.
The redirect work isn’t hard — it is meticulous. Treat it as its own deliverable in the migration project, with an owner and a deadline, and the risk is managed. How it fits into the rest of the switch is described in our comparison with Magento and on the platform page.
Next steps
The SEO work is one of the points we cover in our free migration analysis: we look at your URL structure, your organic position and your current platform and show concretely how a move to HDL Commerce would work without your traffic taking a hit. Book the analysis here — reply within 4 hours (weekdays).
