301 Redirects Explained for People Who Do Not Write Code

If you take one technical concept away from planning a website migration, make it this one. A redirect map is the difference between a move nobody notices and a move that costs you a year of traffic.

What a redirect actually is#

A redirect is an instruction your server gives a browser: the thing you asked for lives somewhere else now, go here instead.

When someone clicks an old link, their browser asks your server for that address. Without a redirect, the server says "404, that does not exist," and the visitor hits an error page. With a redirect, the server says "this moved permanently, here is the new address," and the browser goes there. The visitor usually notices nothing.

Why 301 specifically#

The number is a status code, and the two you will encounter are:

• 301. Moved Permanently. This page has a new address forever. Update your records.
• 302. Found (temporary). This page is briefly elsewhere. Keep the old address on file.

For a migration you want 301, every time. A permanent redirect tells search engines to transfer the accumulated ranking signals to the new URL and to update their index. A 302 tells them to keep indexing the old address and treat the move as temporary, so the new page never fully inherits what the old one earned.

Using 302s during a permanent move is one of the more expensive small mistakes available to you.

What a redirect map looks like#

It is unglamorous. Two columns, one row per URL:

Old URL	New URL
/about-us	/about
/post/spring-guide	/blog/spring-guide
/services-1	/services
/contact-us	/contact

That is the whole artifact. Its value is entirely in completeness, a map covering 95% of your URLs is a map that loses the traffic attached to the other 5%.

The five mistakes that cost real traffic#

1. Redirecting everything to the homepage.

The tempting shortcut: point every old URL at / and call it handled. Google recognises this pattern, classifies the redirects as soft 404s, and passes no value. You get the appearance of a solution with none of the benefit, and visitors who clicked a link about a specific service land on your homepage and leave.

Redirect to the closest genuine equivalent. If there is none, redirect to the most relevant category page.

2. Redirect chains.

/old → /newer → /newest. Every hop dilutes signal slightly and slows the page. Chains accumulate when a site is migrated more than once and nobody flattens the earlier rules.

Fix by pointing every old URL directly at its final destination.

3. Forgetting non-page URLs.

Images, PDFs and downloads have URLs too, and they can rank and earn links. A menu PDF, a price list, a whitepaper, check whether any of them get traffic before you let them 404.

4. Ignoring the www and https variants.

http://, https://, www. and non-www. are four distinct addresses to a search engine. All should resolve to one canonical version with a single redirect hop.

5. Never verifying.

Building the map is half the job. After launch, re-crawl the old list and confirm each URL returns 301 and lands on a working page. Mistakes at this stage are cheap to fix and expensive to leave.

How long to keep redirects in place#

Longer than you think. Google needs to re-crawl every old URL to discover the redirect, and low-priority pages can wait months.

The practical answer: keep them permanently. They cost nothing to leave in place, and old links on other people's websites will keep sending you visitors for years. Removing redirects after twelve months is a common way to lose traffic that had already been successfully preserved.

Checking your own redirects#

You do not need specialist software for a spot check. Open your browser's developer tools, go to the Network tab, and load an old URL. You will see the status code, look for 301, then a 200 on the destination.

For a whole site, a crawler like Screaming Frog will test a list of URLs in bulk and flag chains, loops and 404s.

The short version#

A 301 tells search engines a page moved for good and its earned value should follow. A complete, chain-free map of old-to-new URLs, verified after launch and kept in place indefinitely, is what makes the difference between a migration that preserves your traffic and one that donates it back to your competitors.