How long do 301 redirects have to stay in place?

[SEOmoxy]

For a large retail site we have plenty of "old" pages that are 2-3 years old and still have 301 redirects to a new page.  After a search engine has recognized a 301 redirect and dropped the "Old" URL from the index and started displaying the "New" URL, is it safe to delete that old page and thus remove the 301 redirect?

[ShaMenz]

Hi Jamie,

Search engines are not the only place you may find links to your pages. Actually, if you have done a good job of promoting your pages across a variety of channels, there should be links out there in a range of different places.

You will find a more detailed answer I wrote on this question about removing 301 redirects.

Hope that helps,

Sha

[AdoptionHelp]

Short answer: Leave them up until you're sure that all the links pointing to your 301 have been updated or removed.

[mcglynn]

The answer depends on whether there exist any links in the search engines' link graphs that point to those old product pages.

If you have offsite links to old pages, your 301s need to stay in place. Otherwise, whatever link juice is passed from those 3rd-party sites will stop being credited to your new product pages. If there are a significant number of such links, your new pages could drop in the rankings.

(To find links to those old product pages, use OSE.)