301 Redirect: the guide to changing URLs without losing your SEO

A 301 redirect is a server response signalling that a page has changed address permanently: visitors and search engines are automatically sent to the new URL, which inherits the SEO authority built up by the old one.

Since 2016, Google has confirmed through Gary Illyes that 3xx redirects no longer cause any loss of PageRank, whereas a migration without redirects can wipe out years of SEO in a matter of weeks.

At Nexus Synergy, a WordPress and SEO agency, roughly 50% of our projects are rebuilds handled with a systematic 301 redirect plan: this guide details the method we apply to change URLs without breaking traffic.

A 301 redirect tells browsers and search engines that a page has moved for good. It automatically sends the visitor to the new address, passes on the authority built up by the old URL and prevents 404 errors. Done right, it protects your traffic during a rebuild. Done wrong, it can destroy it.

At Nexus Synergy, a WordPress and SEO agency, the topic comes up on one project out of two, because around 50% of the sites we deliver are rebuilds or takeovers, all shipped with a complete 301 redirect plan. This guide covers the definition, the use cases, how it differs from 302, 307 or 410 codes, how to set it up on WordPress and at server level, and the checks to run after launch.

What is a 301 redirect and how does it work?

A 301 redirect is an HTTP status code, meaning a standardised response the server sends to the browser before the page content itself. The 301 code, named "Moved Permanently", means the requested resource has permanently changed address. According to Mozilla's MDN documentation, the server provides the new URL in a header called Location, and the browser follows it without the visitor having to do anything.

The mechanics come down to four steps:

• Initial request: the browser or bot requests the old URL from the server
• 301 response: the server returns the status code and the new address in the Location header
• Switch: the browser loads the new page, at worst the user notices a slight delay
• Index update: Google gradually replaces the old URL with the new one and transfers the signals to it

One detail changes everything: the browser caches a 301 redirect, sometimes for months. A 301 set by mistake therefore stays sticky, even after it is removed on the server side. That is why we never set a permanent redirect "just to test": when the move is not final, a 302 does the job without committing the future.

When should you set up a 301 redirect?

The rule is simple: as soon as a URL that exists changes or disappears, it should 301-redirect to its closest equivalent. Every address indexed by Google is an asset, because it has built up age, rankings and often inbound links.

The classic situations that call for 301 redirects:

• Site rebuild: the new structure changes the URLs, each old address must point to its replacement
• Domain change: acquisition, rebrand or moving from .com to .fr
• Switch to HTTPS: every http:// URL must move to its secure version
• Content merge: two similar articles combined into a single, stronger guide
• Page removal: the discontinued product redirects to its category or to a relevant alternative
• Technical standardisation: www or non-www version, trailing slash, uppercase letters in URLs

The SEO stakes are direct. Without a redirect, the old URL returns a 404 error, Google eventually deindexes it and the links pointing to it no longer pass anything on. With a 301 redirect, the authority follows the move: Gary Illyes, an analyst at Google, confirmed as early as 2016 that 3xx redirects no longer cause any loss of PageRank. For a long time, though, SEOs believed a redirect lost around 15% of authority, a belief inherited from older Google statements: that debate has been settled for almost ten years. Your inbound links therefore keep working, provided they are redirected cleanly. To understand how much these links weigh in your authority, read our guide on what a backlink is.

301, 302, 307, 410 redirect or canonical tag: which one to choose?

The 301 redirect is only one response among several codes and signals that handle a page moving or disappearing. Choosing the wrong tool sends a contradictory signal to Google, and this confusion turns up in almost every audit we run. The table below compares the five options you will meet in practice:

Three lessons emerge from this comparison:

• A lingering 302: a temporary redirect left in place for months ends up treated as a 301 by Google, but you have lost control of the timeline
• An owned 410: when content has no replacement, this code is more honest than a forced redirect to an unrelated page
• A misunderstood canonical: this tag, a line of code that designates a page's reference version, remains a suggestion Google can ignore

The hierarchy is therefore clear. A 301 redirect is binding on every browser and every bot, whereas the canonical merely suggests. In our view, the canonical never replaces a 301 when the old page has no reason to exist any longer: as long as both URLs respond, you keep alive a doubt that Google will sometimes settle against you. And beware of tools that set 302s by default, like some domain managers: we regularly come across them during site takeovers, set years earlier without anyone remembering.

How do you set up a 301 redirect on WordPress and at server level?

On WordPress, which powers 43.5% of websites according to W3Techs (2026), you can choose between accessible plugins and server-level rules. The right tool depends on the volume of URLs to redirect and your technical comfort.

• Redirection plugin: free, with a built-in 404 error log, perfect up to a few hundred rules
• Rank Math or Yoast SEO Premium: the redirect module is included in the SEO tool already installed, handy for centralising everything
• .htaccess file: the rules run at the Apache server level, before WordPress even loads, so faster
• Nginx configuration: the return 301 directive in the config file, reserved for those who control the server
• Cloudflare: Bulk Redirects apply before the request even reaches your hosting, useful for large volumes

Honestly, for a 30-page brochure site, the Redirection plugin is more than enough. Server-level rules become worthwhile as the volume grows, because hundreds of redirects handled in PHP by a plugin add load to every request. But watch out with .htaccess: a single badly written line in this Apache configuration file and the whole site throws a 500 error. Always back up the file before editing it, and test straight away.

One classic trap is worth naming: redirecting via JavaScript or a meta refresh tag. These browser-side methods are slow, poorly interpreted by bots and carry no HTTP-code value. We systematically replace them with genuine server-side 301 redirects during site takeovers.

The 301 redirect plan for a rebuild: our 4-step method

A rebuild without a redirect plan is the fastest way to lose your SEO. At Nexus Synergy, around 50% of our projects are rebuilds or takeovers, and the 301 redirect plan is a given, just like the mockup. Here is the method we run every time:

• Inventory: a full crawl of the old site with Screaming Frog, cross-referenced with the pages Google Search Console knows about and those receiving backlinks
• Mapping: each old URL is paired in a spreadsheet with the new page closest in intent, never "to the home page by default"
• Prioritisation: the URLs that generate traffic or receive inbound links are handled and checked first, the rest follows
• Post-launch testing: the moment it goes live, we recrawl the list of old URLs to check that each one returns a 301 to the right target, in a single hop

The mapping spreadsheet is the heart of the setup. Four columns are enough: old URL, new URL, priority, verification status. Our absolute rule: no indexed URL leaves the spreadsheet without an explicit decision, redirect to an equivalent, kept identical or knowingly removed with a 410. It is tedious on an 800-page site, no one will say otherwise. But every rushed line is a ranking that can vanish at launch.

This rigour pays off. The rebuild of Maison Laurent, migrated with a complete mapping of its URLs, led to +450% of organic traffic in 8 months. And the plan serves twice, because the testing also reveals the internal links still pointing to old addresses.

If you are preparing a migration, our guide on website redesign details the other tasks to anticipate. And when visibility is a project goal, this plan fits into a broader SEO engagement, with ranking tracking before and after the switch.

Redirect chains and loops: the mistakes that dilute the signal

The 301 redirect protects your SEO, but it degrades when it stacks up. A redirect chain, meaning a URL A that redirects to B, which itself redirects to C, slows the visitor down and weakens the signal passed on at each hop. The Google Search Central documentation states that Googlebot follows up to 10 hops before giving up, but each step adds a full network round trip, which costs you dearly on a mobile connection. Three rebuilds in ten years without cleanup, and your visitors cross four servers before reaching the page.

The faults we correct most often in audits:

• Accumulated chains: three successive rebuilds without cleanup, and some URLs go through four hops before arriving
• Infinite loops: A redirects to B which redirects to A, the browser shows an error and Google indexes nothing
• Mass redirects to the home page: Google treats them as soft 404s, pages deemed missing despite their 200 code, and the authority evaporates
• Outdated internal links: the menu and content still point to redirected URLs instead of the final addresses

Good practice comes down to one sentence: every redirect must lead to its final target in a single hop, and internal links must be updated to that target. Let's be honest on one point: even a perfect redirect plan does not prevent ranking fluctuations for a few weeks after a migration, while Google recrawls and reassigns the signals. This wobble is normal. What is not normal is traffic that still has not recovered after two months.

How do you test your 301 redirects and track 404s after a migration?

Setting redirects is not enough, you have to prove they work. Testing happens in two phases: a live check on launch day, then several months of monitoring in Google Search Console.

For the immediate check:

• httpstatus.io: paste a list of URLs and read the response codes and the number of hops
• Screaming Frog in list mode: import all the old URLs and check code, target and chains in a single crawl
• Private browsing: test the strategic URLs by hand, the browser cache does not skew the result

Then comes the monitoring. In Google Search Console, the Pages report lists URLs marked "Not found (404)": after a migration, check it every week for 3 months, because Google discovers the oversights as it crawls. Every 404 that appears is a missing redirect to add. The stakes actually go beyond the classic engine: in 2026, 48% of Google queries trigger an AI Overview, and these generated answers cite specific URLs. If yours change without a 301 redirect, the citations you have already earned point into the void. How long should you keep the redirects? John Mueller, a Google spokesperson, recommends at least a year; we advise never removing them as long as the old URL is still getting visits or links. This check is one of the verifications described in our guide on how to do an SEO audit, and it is often what explains sluggish traffic months after a rebuild.

One last reflex, almost always forgotten: the XML sitemap, the file that lists your site's pages for the engines. After the switch, it must contain only the new URLs, never the old redirected addresses. A sitemap that mixes the two sends contradictory signals and wastes crawl budget, meaning the time Googlebot is willing to devote to your site. Two minutes of checking, weeks of recrawling saved.

Frequently asked questions about the 301 redirect

Does a 301 redirect cause a loss of SEO?

No, a properly set 301 redirect no longer causes any loss of PageRank: Gary Illyes, an analyst at Google, confirmed this publicly as early as 2016. The authority of the old URL is transferred to the new one, including what the backlinks bring. Ranking fluctuations do remain possible for a few weeks, however, while Google recrawls everything and reassigns the signals. The real losses come from execution mistakes: a redirect to an unrelated page, chains of several hops, or forgotten URLs that end up as 404s. In other words, it is not the 301 redirect that costs you SEO, it is its absence or poor implementation.

What is the difference between a 301 redirect and a 302 redirect?

The 301 redirect is permanent, the 302 is temporary, and that nuance changes Google's behaviour. With a 301, the engine replaces the old URL with the new one in its index and transfers the authority to it. With a 302, it keeps the original URL in the index, because it expects it to come back. Use the 302 for maintenance, a test or a short operation, and the 301 for any permanent move. The classic trap is leaving a 302 in place for months: Google ends up treating it as permanent, but you have lost consolidation time with no benefit.

How long should you keep a 301 redirect?

At least a year, that is John Mueller's public recommendation at Google, and we advise longer still. Google needs to recrawl the old and new URL several times to consolidate the signal transfer, which takes months on a large site. And the engine is not the only party involved: backlinks, bookmarks or old print materials keep pointing to the old address well after the migration. At Nexus Synergy, the rule is simple: a redirect is only removed if the old URL no longer receives visits or links, which you can verify in the server logs and in Google Search Console.

How do you set up a 301 redirect on WordPress without touching the code?

Yes, it is possible with a plugin, without opening a single server file. The free Redirection plugin handles rules one by one or by CSV import, and logs the 404 errors your visitors hit. Rank Math and Yoast SEO Premium also include a redirect module, handy if the extension is already in place. The process comes down to three steps: create the rule, paste the old URL then the new one, save and test in private browsing. Reserve the .htaccess file or the server configuration for large migrations, because a syntax error in these files can make the entire site inaccessible.

What should you do with the 404 errors spotted in Google Search Console after a migration?

Treat them as a list of missing redirects, not as a fate. Open the Pages report, the "Not found (404)" section, and export the URLs concerned. For each one, two options: add a 301 redirect to the equivalent page if the content still exists, or leave a 404, or even return a 410 code, if the page has no relevant replacement. Redirecting every error to the home page is a false good idea, because Google treats these redirects as soft 404s. After a migration, this weekly check for 3 months is enough to catch almost all the oversights in the initial plan.

Can you redirect all the old pages to the home page?

No, that is precisely the mistake that ruins the benefit of a redirect plan. When an old URL is sent to a page unrelated to its content, Google classifies it as a soft 404: the redirect is ignored and the authority built up disappears. Good practice is to redirect each page to its closest equivalent in intent, for example a removed product to its category, an outdated article to the guide that replaces it. The home page only receives the URLs that genuinely have no other logical landing point. This mapping work takes time, but it is what preserves your rankings.

Preparing a rebuild, or seeing 404s all over the place after a migration? Nexus Synergy offers a first SEO and performance audit in three parts (technical, SEO, AI visibility), with a firm quote within 24 hours. Tell us about your project: we will quickly know whether your 301 redirects are working for you or against you.