Matt Cutts, Distinguished Engineer from Google posted a video update on Tuesday (2/25/13) on the topic of “What Percentage of PageRank is Lost Through a 301 Redirect?”
What Matt Cutts clarified yesterday is that no extra PageRank is lost when using a single 301 redirect.
In the video he says “the amount of PageRank that dissipates through a 301 is currently identical to the amount of PageRank that dissipates through a link.” It has been common knowledge for a long time that when web page A links to web page B, although minimal, some amount of PageRank is lost. However, it was believed that more PageRank would be lost if a 301 redirect is used.
With a 301 redirect, web page A is linking to web page B that 301 redirects to web page C. Due to past comments by Google; it was believed that a slight amount more of PageRank was lost when a 301 redirect was used to connect web page A to web page C when compared to a direct link. This is certainly not the case. According to Google, a single 301 redirect does not pass any less PageRank to the destination page when compared to a direct link.
However; it is also important to note that he says:
As always, it is important to be cautious and look at all of the factors before implementing any 301 redirects, such as:
It is important to ensure that you take an in-depth look at the reasons to and possible outcomes of implementing redirects. You can find the video from Matt Cutts here: http://www.youtube.com/watch?v=Filv4pP-1nw