There will always be times when webmasters need to change a website’s urls, temporarily point one page to another or take down a page (permanently or for routine maintenance). When encountered with these types of situations, many webmasters are unsure of how to handle the task at hand. As these issues are fairly common, we have compiled a bit of information about common HTTP status codes and their uses for you to refer to as needed.
We’ll start with the basics. This HTTP status code indicates that the request was successful. You want this for all of your site’s pages (the ones that you want indexed).
301 Moved Permanently
If at any time a URL of a page changes (maybe from a site redesign or a new page has been created to replace an old one), it is recommended to use a 301 Moved Permanently redirect. This code tells search engines that the page should be permanently redirected to the new page. This also helps to make sure users are sent to the correct page.
This code should only be used for temporary redirects. The word ‘temporary’ is key. There are very few instances where this type of redirect should be used, but unfortunately it is the easiest to implement, so when trying to implement permanent redirects, we often see that a 302 Found was implemented instead. With this HTTP status code, Google will continue to crawl and index the original URL.
404 Not Found
A 404 Not Found status code means that the page does not exist. It could have existed in the past, but does not presently. In most instances, websites will issue the generic 404 page when the requested page cannot be found. However, these pages do not have your site’s navigation and can’t help the user find the information they were originally looking for; this why it is always recommended to create a custom 404 page.
503 Service Unavailable
Many of you have tired to go to a website and it is down; perhaps due to maintenance tasks taking place. The best thing to do in this situation is to return a 503 HTTP status code. This tells search engines that the site is only down temporarily. Similar to 404 pages, you should also create a custom message explaining when the site might be available again.