Ladies and gentlemen, the days of unlimited broadband may be numbered in the United States, and we're not talking wireless this time -- AT&T says it will implement a 150GB monthly cap on landline DSL customers and a 250GB cap on subscribers to U-Verse high speed internet starting on May 2nd. AT&T will also charge overage fees of $10 for every additional 50GB of data, with two grace periods to start out -- in other words, the third month you go over the cap is when you'll get charged. DSLReports says it has confirmation from AT&T that these rates are legitimate, and that letters will go out to customers starting March 18th. How does AT&T defend the move? The company explains it will only impact two percent of consumers who use "a disproportionate amount of bandwidth," and poses the caps as an alternative to throttling transfer speeds or disconnecting excessive users from the service completely. Customers will be able to check their usage with an online tool, and get notifications when they reach 65 percent, 90 percent and 100 percent of their monthly rates.

We just spoke with AT&T representative Seth Bloom and confirmed the whole thing -- rates are exactly as described above, and the company will actually begin notifying customers this week. He also told us that those customers who don't yet have access to the bandwidth usage tool won't get charged until they do, and that AT&T U-Verse TV service won't count towards the GB cap.

Update: What prompted this change to begin with? That's what we just asked AT&T. Read the company's statement after the break.

We are committed to providing a great experience for all of our Internet customers. Less than 2 percent of our Internet customers could be impacted by this approach - those who are using a disproportionate amount of bandwidth. We will communicate early and often with these customers so they are well aware of their options before they incur any additional usage charges.

The top 2 percent of residential subscribers uses about 20 percent of the bandwidth on our network. Just one of these high-traffic users can utilize the same amount of data capacity as 19 typical households. Lopsided usage patterns can cause congestion at certain points in the network, which can slow Internet speeds and interfere with other customers' access to and use of the network. Our new plan addresses another concern: customers strongly believe that only those who use the most bandwidth should pay more than those who don't use as much. That's exactly what this does – and again, 98% of our customers will not be impacted by this.

via AT&T will cap DSL and U-Verse internet, impose overage fees update - Engadget.