We all know that your website’s ‘page not found’ page is important. People see it every day. Sometimes very important people. It should never just have some geeky message featuring the number 404. Offering people the chance to find their way to where they thought they were going is just courteous, and makes obvious business sense too.
But there’s an SEO-related reason for turning your ‘page not found’ page into a useful resource. The less helpful a landing page is, the more chance that a visitor from Google will return to where they came. And every page on your website which sends people straight back to Google probably has a detrimental effect on the whole website’s ranking.
You can’t stop people seeing your ‘page not found’ page. I’d hope that you don’t have any broken links on your own site (have you checked recently?). I’d hope that you try very hard to get any broken external links fixed, or if not, that you redirect them. But however diligent you are, some people will just (mis-)type non-existent addresses into their browser.
So make sure your ‘page not found’ page does everything it can to keep people from leaving the site. Links to your most attractive or newest content should be just the start. Some SEO experts suggest having as many as a couple of dozen. Also, ensure that your ‘page not found’ page actually tells the outside world that’s what it is, by returning a ‘404’ HTTP status code. You don’t need to know what this involves, but go to this tool and enter your domain name followed by some junk (e.g “www.bmon.co.uk/3rGu-xDvvN34”). If the status code returned isn’t 404, get your web designer to sort it out.