AT&T's no-contract wireless service Aio is preparing to stretch its legs next month following an initial launch in a handful of markets earlier this year. The service will be available to all US customers starting mid-September according to a press release on the matter.

At present, Aio is available in select markets across Florida, Texas and the Metro-Atlanta area through more than 200 dealer-owned stores. Additionally, those in the Chicago area can activate service online through the company's website.

Aio offers customers three basic plans which all include unlimited talk, text and data. Pricing starts at $40 and tops out at $70 per month and includes all taxes and fees.

The cheapest option is the Aio Basic plan. Limited to feature phones only, this plan includes 250MB of high-speed data (speeds throttle after the cut-off point). $55 per month will deliver the Aio Smart plan and 2GB of high-speed data before throttling kicks in. Finally, Aio Pro offers 7GB of high-speed data at $70 per month. The Smart and Pro plans work with basic or smartphones.

The company also offers tablet data plans starting at $15 per month for 250MB of high-speed data.

New subscribers that sign up before September 29 will receive their third month of service free of charge. Customers can select from one of Aio's smartphones or basic phones or instead, bring their own handset. The latter option will only require the purchase of a new SIM card.