How T-Mobile’s roaming data caps would affect you

Tmo News has it that T-Mobile is about to restrict roaming data usage to cut down on the amount of packets its customers consume when off the carrier’s networks. If true, the new restrictions could affect a lot of T-Mobile’s customers, though the size of the impact on each customer may be small.

Like every other operator, T-Mobile uses a combination of its own and other operators’ networks to provide nationwide coverage, which in T-Mobile’s case means 96 percent of the U.S. population. But T-Mobile is also the smallest of the U.S. national carriers and has the smallest in-house network, meaning it relies more heavily on roaming than its competitors. While T-Mobile has filled in its metro market footprint extensively much of the vast areas in between cities and towns lack the carrier’s infrastructure.

For customers that work in a city but commute in from the countryside, or for road warriors who make extensive use of the nation’s highways, this could have a big impact. Not only will their data at home be capped at between 10 MB and 200 MB a month, depending on their data plans, but they would have no option to boost their monthly allotment once they hit their caps, according to Tmo News – their data service would simply stop until they re-entered T-Mobile coverage or a new billing cycle kicked in.

That said, these customers weren’t exactly getting great data service in the first place. T-Mobile’s HSPA+ networks are confined to its own footprint, and while some of its partners have 3G networks, they don’t necessarily sell T-Mobile access to them. Once leaving T-Mobile’s coverage footprint, most customers usually can tap mere 2G speeds: GPRS or, at best, EDGE. Trying to use a smartphone with dial-up modem speeds is often an exercise in futility.

Still, a lot of customers have probably come to rely on those 2G roaming networks for basic connectivity when outside of the T-Mobile footprint. The operator has given them some leeway in their caps, but you can easily eat up 10 MB in about 30 minutes with a 30 kbps connection.

T-Mobile currently doesn’t distinguish between its own networks and those of its roaming partners on its coverage maps. If these new caps go into affect, though, it will have to.

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