The different services that are discussing include the following:
a. Ring Central Fax: They do a nice and appreciable job in integration of the fax features with Gmail with the local and toll free numbers available in UK, USA, Canada and most recently UK. There are a lot of fax features that the service is packed up with. Source for read this post.
b. E-Fax: The name is one of the better and top rated services currently in the entire World. This company has got its operational headquarters in as many as 40 countries all around the world which makes it the hugest fax company of the world. The users can create their account within no time at all and choose between local and toll free numbers available within an area.
c. MyFax: The plans of this company date back to a nice point of time and are in for users at a very reasonable price. There might be some advanced features not available. This company; hence, is perfect for the newbie interested in only basic fax issues via Google and Gmail. There might be a drawback as mentioned of lacking some advanced features; however, it does land quickly among the top, very top Gmail fax services; only due to its reliability and integration.