Starting Sunday, January 22, AT&T customers will have to fork over a little bit more for mobile data packages. The company announced that it is raising its package prices by $5 each per month, but it is also increasing the size of those data packages, which offsets the cost a smidge.

The current plans offer 200 MB for $15 per month or 2 GB for $25 per month. Mobile hotspot customers paid $25 per month for the 2 GB plan and another $20 for 2 GB of hotspot data, for a monthly total of 4 GB for $45.

Moving forward, there will be three new plans for smartphones: 300 MB for $20 per month; 3 GB for $30 per month; and 5 GB for $50 per month. The $50 plan also includes mobile hotspot/tethering.

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AT&T has increased the cost of its monthly data plans for tablets, too. The prices mirror those of the smartphone plans, which cost $15 for 250 MB, $30 for 3 GB, or $50 for 5 GB.

Looking at the cost per megabyte, AT&T's new smartphone data bundles come in slightly cheaper than the old ones. Previously, for $1 you could get 13 MB on the $15 plan; 80 MB on the $25 plan; and 88 MB on the $45 plan. For that same dollar, the new plans will offer 15 MB on the $20 plan, and 100 MB on the $30 or $50 plans.

AT&T is allowing existing customers to keep their existing plans, however, including the entry-level 200 MB for $15 option. Of course, if you exceed your data limit, AT&T will hit you with an overage charge. The overage charges remain the same at $10 per gigabyte over the monthly allotment.

"Customers are using more data than ever before," said David Christopher, chief marketing officer, AT&T mobility and consumer markets. "Our new plans are driven by this increasing demand in a highly competitive environment, and continue to deliver a great value to customers, especially as we continue our 4G LTE deployment."

AT&T points out that it will send SMS alerts to customers as they near and/or surpass their monthly limits in order to cut down on the possibility of incurring overages. It also encourages customers to keep their Wi-Fi radios on, as smartphone and tablet customers have free access to AT&T's 29,000 Wi-Fi hotspots nationwide.

Any way you care to slice the data points, new customers will still have to pay $5 more per month to access data--whether it be HSPA+ or LTE--from AT&T. And that stinks.

(Sprint and T-Mobile have packages that cost a bit less than AT&T's new plans, but Verizon's still cost a bit more than AT&T's new plans.)

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