The company will also remove the label from Google Docs, Calendar and Talk which had previously been using the label to show Google was still improving the software.
According to Matthew Glotzbach, director of product management, removing the label lets Google target companies with a policy that does not allow them to deploy beta software.
Gmail had been in beta ever since it was introduced five years ago.
Google products that have already dropped the label include the Chrome Web browser, unveiled in September. Google Scholar, which lets users search for scholarly papers, remains in beta.