When AT&T resurrected unlimited data plans, it also introduced a feature it had shunned the first time around: letting subscribers use their phone as a mobile hotspot (AKA “tethering”), but only up to 10 GB per month. But there’s a flaw in AT&T’s execution that prevents users from knowing how much tethering data they’ve actually used.

AT&T’s new “unlimited” plans have a total monthly threshold of 22 GB, but only 10 GB of that can be used for tethering. Problem is, the wireless giant doesn’t separate hotspot data from the rest, meaning there’s no way to tell when you’ll hit that 10 GB limit, after which AT&T can slow tethering data down to a crawl.

Reader Michael uses one of these plans, and was annoyed to discover that he can’t keep track of how much of that data cap he’s used. He says he contacted various AT&T support departments, all of which confirmed his suspicion that while the carrier keeps track of his data use through his phone and when using the phone as a hotspot, customers have no way to access this information.

“I was told that their system keeps track and will throttle customers but that neither I, nor any AT&T rep has the ability to check on the amount of data used over tethering,” he wrote to Consumerist.

Michael is an iPhone user, and iOS does keep track of this information, but it tracks data use over the lifetime of the phone or between manual resets. He would have to remember to reset the meter exactly when the billing cycle rolls over. That might not be all that useful, anyway.

“I suspect [the iPhone’s] number will be different from the AT&T internal system,” he speculates.

Consumerist contacted AT&T and found that what the support employees told Michael is true. No one can tell him how much data he’s used through tethering.

“AT&T wireless customers can check their overall data usage per line through the MyAT&T portal either online or through the app on their device,” a spokesperson for the carrier told us. “We do not currently break out the tethering usage as a line item but plan to do so later this year.”

There you have it, AT&T unlimited customers. The feature isn’t available in time for the actual debut of tethering on unlimited accounts, but it will be at some point in 2017.

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