A redesign that succeeds visually can lose half the organic traffic in three weeks. The cause is almost always the same: the addresses changed and nothing links the old ones to the new ones.
The redirect plan is not an end-of-project task. It is prepared before go-live and monitored for a month afterwards.
Before: the exhaustive inventory
You cannot redirect what you do not know about. Four complementary sources, to be cross-referenced.
A crawl of the current site, which gives every page reachable through navigation. That is the base, and it is incomplete.
The sitemap, which sometimes contains pages not linked in the navigation.
Search Console, over twelve months, which reveals the pages receiving organic traffic, including those the crawl did not find. This is the most valuable source: it tells you what has value.
The server logs over three months, which show the addresses actually requested, including through old external links you had forgotten about.
The union of those four sources gives you your scope. On a mid-sized catalogue, expect several thousand URLs, a share of which deserve no treatment at all.
Prioritise rather than treat everything
Redirecting ten thousand pages one by one is neither possible nor useful. Three levels of treatment.
General rules. If the URL structure changes systematically, one rule covers thousands of pages. That is the case when you drop a prefix, change the identifier format, or move from one structure to another.
Individual redirects. For pages that follow no rule: renamed CMS pages, merged categories, consolidated products. Focus them on pages with traffic or inbound links.
410 treatment. For what disappears with no equivalent. That code signals a deliberate removal and speeds up removal from the index, which a 404 does more slowly.
A useful marker: on most redesigns, 90% of organic traffic concentrates on less than 20% of the pages. Those are the ones that need individual verification.
301 Redirect Manager for PrestaShop 8 & 9301, regex, wildcard, 404 monitoring and auto redirect on slug change€49.00
The mapping rules
Four principles, the first of which is the most often broken.
A redirect points to the closest equivalent, never to the home page. A mass redirect to the home page is treated as a soft error: the engine sees that the destination has nothing to do with the request, and the benefit is nil. For a discontinued product, redirect to a replacement product or, failing that, to its category.
A redirect is permanent. The 301 code passes the value of the old page. A temporary redirect does not, and it leaves both addresses coexisting in the index.
A redirect is direct. No chains: if address A was redirected to B last year and B becomes C today, update the A rule to point to C rather than stacking.
The destination has to answer with a 200. Redirecting to a page that is itself in error is a frequent case when the mapping is built before the new site is finished. Check afterwards, not before.
Switchover day
Order of operations, each one conditioning the next.
- The redirects are in place before opening, tested on the staging environment with the real addresses.
- The sitemap is regenerated with the new addresses only, and submitted.
- Internal links point to the new addresses, not to the old ones that redirect. A site where every internal link goes through a redirect slows its own crawling and dilutes value.
- The robots file is checked, particularly if the staging environment was blocking indexing. A forgotten blocking directive in production is the most expensive accident of a redesign.
- The canonical tags point to the new addresses.
The following fortnight
This is the period where everything is decided, and where most projects let their attention slip.
The 404 errors in Search Console, to be checked every two days. Every new 404 signals an address missed in the mapping.
The server logs, filtered on 404 and 500 codes. They surface faster than Search Console and include the crawlers’ requests.
Organic traffic, compared with the same period last year rather than with last month. A drop of 10 to 20% for two to four weeks is normal, the time engines need to process the redirects. A drop of 50% signals a problem.
The positions on your twenty main queries, recorded before the redesign and tracked after.
How long to keep the redirects
A frequent question. Engines pass the value fairly quickly, but external links and visitors’ bookmarks never update themselves.
The prudent rule: keep the redirects indefinitely as long as they raise no performance issue. A file of a few thousand well indexed rules costs nothing. What costs is the chains accumulated over several successive redesigns, which have to be flattened periodically.
The classic mistakes
Redirecting every old page to the home page, mentioned above, and by far the most destructive. Forgetting the versions with and without a trailing slash, which are two distinct addresses. Ignoring images, whose addresses also change and which can receive traffic. And leaving the URL parameters of the old filters untreated, which produces a significant volume of errors.
The 301 Redirect Manager for PrestaShop handles this chain on PrestaShop 8 and 9: bulk import of the mapping, pattern rules alongside individual redirects, detection of chains and loops, and tracking of the 404s encountered so the plan can be completed day by day.