U.S. Cellular also has joined the $100 a month unlimited plan party. The plan offers unlimited national calling, and in conjunction U.S. Cellular offers unlimited texting for $14.95 and an unlimited “easyedge” data package for $9.95.

“We recognize that cell phones are critical to helping customers keep connected with the people and activities that matter most to them,” said Jay Ellison, executive vice-president and COO of U.S. Cellular, in a statement.

However, the company has said that it doesn’t expect a huge number of its 6 million subscribers to jump at the $100 unlimited offer, saying that high-volume callers represent a small percentage of its customers.

Earlier this week, Verizon Wireless announced an unlimited calling plan for $99.99. AT&T and T0Mobile quickly followed suit.