When will the new Code Geass season come out in America?

There are no additional seasons of Code Geass planned, just some OVAs. I'm assuming you're referring to the 4 episode Boukoku no Akito spin-off OVA, since people often refer to it as a "third season."

This OVA has not yet been licensed for release in America, so there is no release date. It will almost definitely be licensed eventually, but until it is, there is absolutely no way to even guess when it might be released. The first episode was only just released theatrically in Japan on August 4th (with the second episode getting a theatrical release in Spring 2013), so it won't even be available to watch online for several months (until the as yet unscheduled Japanese DVD/BD release happens), let alone get an official release in America anytime soon. If I had to take a guess, I'd say it will be 2 years minimum before an "official" American release, very possibly longer, depending on how long the series takes to release in Japan. Since more than 6 months will pass between the release of the 1st and 2nd episode, it will probably take a long time.

well i hate to tell you this but there isn't a code geass r3 coming out there's a prequel to code geass coming out and it takes place before zero was even born that's what coming out to america code geass r3 doesn't even exist so if there's a site that tells you code geass r3 is coming out in america that site told you a lie and that's the truth sorry about that

To my knowledge, there have only been two seasons and they came out already