Website redesign and SEO: how to do 301 redirects properly

A business has a new, nicer website made. Six months later there are fewer enquiries than before. The site looks better than ever, but nobody finds it from a search engine any more. The cause is often the same, and it can be prevented with one step done before launch.

What happens on launch day

Your old website has addresses. Google has visited them for years. It knows what is on them, and other sites, such as the local paper, an association or a supplier, have linked to them. That accumulated knowledge and trust is attached to the address, not to your business.

When a new website is launched, the addresses almost always change: file extensions disappear, the structure changes, pages are merged. If old addresses are not redirected to the new ones, three things happen at once. Google finds an error page at the old addresses and over time drops them from search results. The new addresses start practically from scratch, because they are new to Google. Links from elsewhere point to an error page.

Years of accumulated value are cut off overnight, and nobody notices on launch day.

Address mapping is the step that prevents this

Before the old site is taken down, a list is made of all its addresses and each one is given a new equivalent. The list comes from Search Console, the old sitemap, visitor analytics and, if needed, the Internet Archive. It is a dull spreadsheet, and it is the most important file in the whole project. When I do a website redesign, this mapping and the redirects are part of the work.

OLD ADDRESS

/palvelut.html

REDIRECT

Permanent redirect (301 or 308)

NEW ADDRESS

/palvelut

The equivalent chosen is the closest matching content, not the home page. If the old page covered bathroom renovations, the redirect belongs on the bathroom renovations page. Redirecting to the home page is an easy shortcut, and it wastes both the visitor and whatever was left of the address.

Permanent or temporary redirect

A redirect is a message to the browser and the search engine about where the content is now. The visitor ends up on the right page automatically and notices nothing. What matters to the search engine is whether the change is stated to be permanent or temporary.

• 301 and 308 mean a permanent move. They are used when an address has changed for good. They are a strong hint that the new address is the right one.
• 302 and 307 mean a temporary move. They belong in situations where the old address is meant to come back into use: a campaign page, a maintenance break, a temporary alternative.
• The difference between 301 and 308 is technical: 308 preserves the original request method, which matters for forms. For an ordinary page, 301 is the established choice.

A temporary redirect is not broken, then, but it tells the search engine the wrong thing if the change was permanent. In practice the old address lingers in search results and the situation clears up slowly or not at all. So check the code, not just that the redirect works in a browser.

What else to do at launch

• Internal links are updated to point straight to the new addresses. A redirect is a safety net for outside links, not a way to handle your own navigation.
• Canonical tags point to the new address. A canonical pointing to the old address is a common and unfortunate leftover that undoes part of the work done.
• A new sitemap is made and submitted in Search Console. The old sitemap is taken out of use.
• The indexing block from the build phase is removed. This is a surprisingly common way to do everything else right and still disappear.
• Important old pages are kept. If a page brought in visitors, its content belongs on the new site, not in the bin because it does not fit the new look.
• 404 errors are monitored after launch. Every error is an address that was left out of the mapping.

Redirects are worth leaving in place permanently. They cost nothing and in practice do not slow the site down, and an old link can turn up years later.

What happens after the move

Even in a well-done move, search results usually fluctuate after the addresses change. Rankings can swing in both directions, because Google has to crawl the site again and match the old addresses to the new ones. Nobody can promise that rankings stay exactly the same, and nobody can say to the day when things will settle.

What can be promised is monitoring. For the first weeks, watch three things in Search Console: whether 404 errors appear, whether the new addresses are being indexed, and whether search traffic stays roughly at the same level. If any of these looks bad, the cause is usually in the mapping.

DO NOT DO A BIG MOVE AND A FULL CONTENT OVERHAUL ON THE SAME DAY IF YOU CAN AVOID IT. WHEN TWO BIG CHANGES COINCIDE, IT IS IMPOSSIBLE TO SAY WHICH CAUSED WHAT.

If the domain name changes too

If the domain name is also changed in the redesign, the risk grows. In that case the redirects are made from the old domain's addresses to the new domain's addresses, both are added to Search Console, the move is reported with the Search Console change of address tool, and the old domain name has to stay valid, otherwise the redirects stop working. Letting the old domain lapse to save money is the most expensive saving possible.

There is a separate article on domain name ownership and email continuity, and it is worth reading before anyone touches the domain.

What if the redesign is already done and traffic collapsed?

The situation can usually be fixed afterwards, and the sooner it is noticed, the less is lost. First work out the old site's addresses. They can be found in Search Console, in old backups or in the Internet Archive. Make the redirects, fix the canonicals, submit the new sitemap and monitor. Recovery takes time, and its length cannot be promised in advance.

If the site still cannot be found after the redirects, the fault may be elsewhere. The seven most common reasons for invisibility are covered in a separate article.