Www or non-www in Google Webmaster Tools

[jacksghost]

I have a newer website that I recently added to GWT and it displays one time as: "www.domain.com", which is fine.

However, I have 3 older websites that were entered in GWT years ago and they are all listed listed twice as: "www.domain.com" and again as "domain.com".  I don't know if they were manually entered twice like that at the time or if Google created both of them automatically somehow.  Right now, GWT shows the same exact site statistics for both of them so I am wondering if it is ok to delete the extra non-www listings from the account.  Under Site Settings, I already have all of our websites set to use the "www" page so I don't think that should be affected.

Any opinions?

[guillermoga]

Hi!

When you choose your preferred domain between www and non-www, you must declare ownership of both. So don't delete any domain from your account. This is most likely the reason you have both domains on your GWT.

Here you can see the GWT Help and verify what I said:

"You may need to verify ownership of both the www and non-www versions of your domain. Because setting a preferred domain impacts both crawling and indexing, we need to ensure that you own both versions"

Cheers.