Redirects are crucial in any redesign in which URLs change or old pages are retired. These redirects ensure a seamless user experience, and also help search engines to update their indexes from old URLs to new URLs and transfer SEO power from old to new pages.

We’ve worked with many site redesigns; many that were seamless and some that suffered unfortunate bumps along the way.  The best practices described here are intended to head off some of the most common errors and glitches we’ve seen in redesigning sites. Here are the SEO Redirect Best Practices we share with our clients:

• Each old URL should be 301 redirected to the most appropriate matching new URL.
• If possible, old URLs that are being eliminated should be 301 redirected to an appropriate new URL.
• If an appropriate new URL does not exist for a page that is being retired, it is okay to allow the page to become a 404 File Not Found error
• Ensure that any broken URLs receive a 404 status code with a nicely-designed 404 error page that helps direct users to new pages
• All internal links to old URLs should be eliminated on the site and replaced with links to the associated new URLs.

For the sake of clarity, we recommend 301 (permanent) server-side redirects. The following are not recommended for most redesign situations:

• 302 redirects – these are only used for rare situations when a temporary redirect is needed
• a sequence of more than one redirection per page.
• meta refresh
• retiring a large number of URLs without redirecting them
• mass redirecting old URLs to the home page.  If a good replacement page doesn’t exist, you can let the old page become a 404 error.

Pay particular attention varying forms of URLs, to make sure that every form of the originating URLs will redirect.  Be sure that all of the following get redirected:

• URLs with and without the WWW
• URLs with and without a trailing slash (folder/ and folder)
• URLs with and without a trailing /index.html
• URLs in all variations of lowercase and uppercase

Follow these best practices and you’ll be helping your users enjoy a smooth transition, and giving your site the best chance of consistent ranks in Google and Bing.