AT&T is trying to convince customers with old unlimited data plans to switch over to one of their fixed data plans. To do this, AT&T will start charging customers that still have these plans an additional $5 per month.

AT&T will increase the price for the legacy unlimited data plan from $30 to $35, CNet reports. The price change will take effect in February.

AT&T stopped offering unlimited data plans five years ago, but customers who stuck with the plan were grandfathered into it, meaning they could keep it.

Customers on the AT&T network have not been able to buy this plan since AT&T eliminated it. In place of unlimited data plans, AT&T has switched over to "buckets" of data, where customers buy a set amount of data per month. If they go over their data allotment, they are charged an overage fee.

A raise of $5 is not much compared to what Verizon's recent increase of $20 on unlimited data plans. Sprint and T-Mobile continue to offer unlimited data plans, but they have raised their prices as well.

Unlimited data customers can go wild with downloading files, streaming music and web browsing, but when they reach a certain amount of data each month their speeds will slow down considerably. AT&T starts slowing down customers' data speeds (called throttling) when they reach 22 GB of usage in a month, 9 to 5 Mac reports.

AT&T blames the rising price in data for the "small price increase" and says this is the first price increase they have made in seven years, according to a press release from the company.

If customers are not willing to accept the price increase, they can cancel their contracts within 60 days of the price increase and AT&T will waive their early termination fees.