Through a focus on customer service, Cox is coming out in front of traditional phone service providers like Verizon, AT&T, and Sprint in recent surveys from J.D. Power & Associates Inc.

Cox is generating about $1 billion a year from its 2.1 million phone customers, with profit margins of 50% to 60%. Nearly 20% of the homes in neighborhoods where it offers phone service have signed up...

In contrast, phone companies only capture about 5% of their potential cable customers.