404 errors on your website: the customer arrives and the page is gone

A Saturday lunchtime in August, at a restaurant with a terrace on the Costa Brava. Every table has a sticker with a QR code for the menu. The couple at table six scan it and their phone shows two words on a white background: “Not Found”. They try again and get the same thing. In the end they wave for a paper menu, which takes a while because there are only three left. Back in spring someone uploaded the new menu to the website under a different file name and deleted the old one, and the stickers were still pointing at the old address. Nobody told the owner, who never scans their own QR code. That is a 404 error, and it is one of the cheapest website problems there is to fix.

What a 404 error is

Every time a page is opened, the server replies with a three-digit number before showing anything. If all is well, that number is 200. A 404 error means “not found”: the website exists and responds, but there is no page at that particular address. The rest of the site keeps working as normal.

Codes starting with 4 mean the problem lies in what was requested, usually the address. Codes starting with 5 mean the server failed. If no page loads at all, it isn't a 404 but a different problem, which we cover in your website is down.

404 and 410: to Google, almost the same

The 404 has a lesser-known cousin, the 410, which means “this has been removed and isn't coming back”. In its documentation on how HTTP status codes affect its crawlers, Google explains that it treats every error starting with 4 the same way, except 429. You can use a 410 when you delete something on purpose, but a 404 does the job.

Why website addresses break

It is hardly ever an obscure technical fault. On small business websites, 404 errors almost always come from one of these:

• A redesign. The new site organises pages differently and the old addresses stop existing. It is the most common cause and the one that wipes out the most rankings.
• A page that gets renamed. “/services/renovations/” becomes “/bathroom-renovations/” because it sounds better, and nobody redirects the old one.
• Something that gets deleted. Last summer's offer, a product you no longer sell, a blog post nobody liked any more.
• Files that get replaced. Menus, catalogues and price lists in PDF uploaded under a new name: “menu-2025.pdf” becomes “menu-2026.pdf”.
• Mistyped links in your own site's menu, on your Google Business Profile, in your Instagram bio, on a flyer or in a link another website gave you.

The tricky part is that almost none of these are visible from the inside. The owner goes in through the home page, the home page works, and there's no reason to think anything is wrong. The person who hits the error is the customer, and customers rarely say anything: they close the tab and keep looking.

Do 404 errors hurt SEO?

The 404 itself doesn't penalise you. Google says so plainly in the Search Console help: 404 responses are not necessarily a problem if the page has been removed without any replacement. Every website collects a few, and someone mistyping an address won't push you down the rankings.

What does cost money is whatever used to live at the broken address:

• That page's rankings. Google removes from its index the addresses that start returning an error. If the page ranked well for a search that brought you customers, it stops showing up.
• The links pointing to it. If the local paper or a supplier linked to that page, the link now leads nowhere and does nothing for you.
• The person who arrives. Someone who had already chosen you, who clicked your ad or scanned your QR code, lands on an empty screen. Most likely they go back to Google and click the next result.

And in AI answers

The same goes for answers generated by AI. Google explains that to appear as a link in AI Overviews or AI Mode, a page has to be indexed and eligible to be shown in Search with a snippet. An address that returns a 404 drops out of the index, so it can't appear there either. If you're working on generative engine optimization so that AI tools cite you, every broken page is one citation fewer.

How to find the 404 errors on your website

There's no need to wait for a customer to tell you. There are three ways to find them, from the simplest to the most thorough.

In Google Search Console

If your site is set up in Search Console, open the Page indexing report. Among the reasons a page isn't indexed you'll find “Not found (404)”, with the list of addresses. Google makes two things clear in its help page for the Page indexing report: it only shows the addresses that returned a 404 in the past month, and it recommends fixing mainly the 404s that you link to yourself or list in your sitemap. The rest are usually addresses other people mistyped, and there's no need to chase every one. We explain how to find your way around the tool in what to check in Google Search Console.

Testing them yourself, with a list

Some addresses Google doesn't always see matter more to you: the ones that are printed or posted outside your website. Open them on your phone one by one:

• The QR codes on the menu, the shop window, the van and your business cards.
• The website link on your Google Business Profile.
• The link in your Instagram bio and the one in your email signature.
• The landing pages of your ads.

It takes five minutes, and it's where a 404 does the most damage, because on the other side is someone who already wanted to buy from you.

With your analytics

If your error page has its own title, such as “Page not found”, your web analytics will tell you how many times it has been shown and which page people were coming from. It's how you find out about the errors nobody reports.

How to fix a 404 error without sending everything to the home page

For every broken address there's one question that settles it: is whatever used to be there now somewhere else?

• Yes, it has moved or has a clear replacement. Set up a 301 redirect from the old address to the new one. A 301 tells browsers and Google that the page has moved for good, and visitors land in the right place without noticing. That's what would have fixed the restaurant: the old PDF address redirected to the new menu, and the table stickers work again without reprinting anything.
• No, it's gone and there's nothing similar. Let it return a 404. That's the correct response and Google understands it. What you need to look after is what the person sees, which is the error page.
• The problem is the link. If it's a typo in your menu, your Google Business Profile or an ad, fix it at the source. And if the link is printed, redirect the mistyped address to the right one.

The temptation is to redirect every error to the home page and forget about it. Don't. In its guide to site moves and migrations, Google asks you not to send many old addresses to a single irrelevant destination, such as the home page, because it confuses users and because those redirects may be treated as a soft 404. Someone looking for the menu who ends up on the home page still hasn't got the menu.

The soft 404: the error page that says everything is fine

A soft 404 is a page that tells visitors what they want doesn't exist, while telling the browser 200, the “all fine” code. Google explains it in its documentation on troubleshooting crawling errors: those pages are excluded from Search, and Search Console flags them by that name. Empty pages can count as soft 404s too, such as a shop category with no products or an internal search that finds nothing.

It's usually down to a theme or plugin that “fixes” errors by hiding them. If they show up in Search Console, check which code your error page returns: it has to be a real 404.

What a good 404 page needs

Even if you redirect everything that has moved, there will always be someone who mistypes an address or arrives through an old link on another site. That's what the custom 404 page is for. Google gives some guidelines in that same documentation, and they match what we see working:

1. Say clearly what has happened. “This page doesn't exist or has moved”, in the site's language and without jargon.
2. Look like the rest of the site, with the same menu, so visitors know they're still in the right place.
3. Offer somewhere to go next: the home page, your services, your prices and your most visited pages.
4. Let people ask or report the problem. A WhatsApp button with the message already written turns an error into a conversation.
5. Return a real 404. If it answers with a 200 or redirects to the home page, it's a soft 404.

Leave out the jokes that lead nowhere and the automatic redirect to the home page after five seconds, which confuses more than it helps. Google sums it up well: these pages exist only for people, because to a search engine they're useless.

If you want to see one, type magnesfactory.com/en/this-does-not-exist into your browser. Ours comes up in the language of the address you typed, with the usual menu, links to services, prices and the blog, and the WhatsApp button.

The broken links that cost the most

Not every error is worth the same. The most expensive ones are those that greet people who had already chosen you.

Ads. Google disapproves ads whose landing page doesn't work. It says so in its destination requirements: a page that returns a 404 when AdsBot, the crawler that checks ads, tries to visit it is grounds for disapproval. If you change your website without checking the campaign's final URLs, your ads can stop overnight, just when you need them most. Why a campaign spends without selling is something we cover in Google Ads spends and doesn't sell.

QR codes and anything printed. You can't fix a QR code without reprinting it. Always point it at a stable address on your site, such as “/menu/”, and never at a file name with a date in it. That way, when the menu changes, the QR code keeps working.

Your Google Business Profile. The website button on your profile is one of the links people nearby tap most. If after a change it points to a page that no longer exists, the customer who was about to call you is left hanging.

Before you change websites, make a list of addresses

Most of the 404 errors a redesign causes can be avoided with a spreadsheet made before the new site goes live:

1. Get a list of every current address: the ones in your sitemap and, from Search Console, the pages that get visits.
2. Next to each one, note which new page it corresponds to.
3. Have the 301 redirects ready before the day of the switch.
4. On launch day, test the whole list: every old address has to end up on its new page.
5. Over the following weeks, keep an eye on the Search Console page report in case one slipped through.

We go into more detail in migrate your website without losing rankings.

Five cases we see all the time

1. The PDF menu with a new name. The QR code on the tables points to a file that's no longer there. A redirect fixes it and a fixed address prevents it.
2. The old website after a redesign. The pages that brought in visits return errors or all go to the home page. The list has to be recovered and the pages redirected one by one.
3. The out-of-stock product that gets deleted. If it's coming back, it's better to leave the page up with “out of stock” and similar alternatives. If it isn't, redirect it to its category.
4. The Google Business Profile link nobody checked after the website changed.
5. Menu links copied from the test version. They worked while the site was being built and stop working the day it goes live.

What a website without broken pages costs

It's all published on our pricing page:

• Your Landing, €100 a month: a single page that explains what you do and collects enquiries, with high-performance hosting and one email mailbox.
• Your Website, €200 a month: up to ten subpages, hosting, two mailboxes and one article a month to keep your presence alive.
• Presence plans, from €400 a month: they include migrating your website and email, which is exactly when most 404 errors appear, plus articles on your site and your Google Business Profile and visibility in AI answers.

All prices exclude VAT and there's no minimum contract: it's billed month by month and thirty days' notice is enough to stop. And if what worries you is the rankings that went with the broken pages, that's a job for SEO.

We'll tell you which addresses on your site return an error

We're three partners working from the Palau Firal in Sant Antoni de Calonge, next to Palamós, with businesses across the provinces of Girona and Barcelona.

Send us your website address on WhatsApp. We'll run a crawler over all its pages, test the link on your Google Business Profile and tell you which addresses return a 404 error and what we'd do with each one. No commitment. If you prefer, write to us through the contact form.