The carrier declined to spell out a timetable for the move, however.
"We are working on bringing it to the iPhone," an AT&T spokesman said by email. "[But we have] nothing else to share at this time."
The move is a counter to rival Verizon, which will let iPhone owners use their smartphone to create a personal Wi-Fi hotspot, which can connect up to five other devices, including tablets and notebooks, to the Internet.
Verizon will provide its tethering for $20 per month, which includes a 2GB data allowance. Each additional gigabyte of data, or a fraction of one, runs another $20 under Verizon's service plan.
Verizon described the Wi-Fi hotspot feature last month when it announced it would sell a CDMA-compatible iPhone 4 starting Feb. 10.
Although AT&T did not confirm a release, it's likely the company will also use iOS' Personal Hotspot rather than release a separate app.
AT&T will also match Verizon's tethering option by adding 2GB of data to its own plan, which previously came with no data allowance of its own. AT&T has bundled iPhone tethering with its Data Pro plan, a $25 per month deal that comes with its own 2GB allotment, since last summer.
For AT&T customers, additional data costs $10 per gigabyte over the amount bundled with its data or tethering plans.
"We want to extend the benefits of an additional 2GB to smartphone customers on our tethering plan," AT&T Mobility's chief marketing officer, David Christopher, said in a statement. "This delivers more value today for the price they're already paying -- and that's what our customers want."
Currently, AT&T's iPhone tethering uses a wireless Bluetooth link between the smartphone and a tethered device, or requires that the user plug the iPhone into a laptop's USB port. Personal Hotspot, however, creates a Wi-Fi hotspot that other devices can access.
AT&T will launch Mobile Hotspot Feb. 13 alongside the $100 Android-powered HTC Inspire 4G -- AT&T's first smartphone to include the app -- and roll out the additional data allowance the same day.
Assuming Personal Hotspot is built into iOS 4.3, the iPhone upgrade expected next month, AT&T won't have to create a version of the Mobile Hotspot app for the iPhone.
Verizon and Apple will begin taking pre-orders from existing Verizon customers for the CDMA iPhone 4 starting at 3 a.m. ET Thursday, midnight PT. The general public can pre-order a Verizon iPhone from Apple on Feb. 9 , and retail sales at Apple, Verizon and Best Buy kick off Feb. 10.
Gregg Keizer covers Microsoft, security issues, Apple, Web browsers and general technology breaking news for Computerworld. Follow Gregg on Twitter at @gkeizer or subscribe to Gregg's RSS feed. His email address is email@example.com.
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This story, "AT&T to offer Wi-Fi tethering for iPhone" was originally published by Computerworld.