AT&T just introduced 2 new 'unlimited' data plans — here's everything you need to know (T)

The carrier has had an unlimited plan for some time, but it had been available only to subscribers of its DirecTV or U-Verse TV services. Earlier this month, it lifted that requirement.

Now it's reworking the costs and features of its offer. The new plans will be available on March 2. AT&T says current subscribers will be able to switch to the new plans.

Here's the rundown:

The first new plan, AT&T Unlimited Plus, starts at $90 a month for a single line. Two lines cost $145 a month, and each additional line costs another $20 a month after that (for up to eight lines). That's down from $100 a month for a single line, plus $40 a month for every additional line, under the previous plan (though that plan previously offered the fourth line for free).
If you subscribe to the Unlimited Plus plan, AT&T will take $25 off the price of a subscription to its DirecTV, U-Verse TV, or DirecTV Now service each month. (AT&T still does not count any of those services against your data cap — a controversial practice known as zero-rating.) AT&T says this is a limited-time promotion and that it will start to apply the $25 credit after two to three billing periods.

You can add a tablet to the plan for another $20 a month and a wearable for another $10 a month.
The Unlimited Plus plan will now include 10 GB of mobile-hotspot data, which lets you use your phone as a portable router. Once you hit that limit, mobile-hotspot speeds will be throttled to 128 Kbps, which is close to slow 2G speeds. Previously, AT&T did not include mobile-hotspot data at all with its unlimited plan.
The Unlimited Plus plan includes "high-definition" video streaming, but to use that you'll have to turn off AT&T's Stream Saver feature, which caps video streams at a less-sharp 480p resolution by default.
Like before, AT&T says it might slow your connection speeds in areas of network congestion if you use more than 22 GB of data in a single pay period.

AT&T is offering a second, more affordable "unlimited" plan called AT&T Unlimited Choice. That starts at $60 a month for a single line, $115 a month for two lines, and another $20 a month for each additional line after that.

However, it caps all video streaming at "about 480p," has no mobile-hotspot data, and throttles all speeds to 3 Mbps, which isn't terribly fast by modern standards. Once again, AT&T says it might slow speeds in areas of congestion if you use more than 22 GB of data in a given month.

In either case, the rates above do not take into account monthly fees and taxes, so they'll be a little more expensive than advertised — a caveat that applies to every carrier but T-Mobile.

You'll also have to enroll in auto-pay billing — otherwise, AT&T says a single-line plan will cost another $5 a month, while a multiline plan will cost another $10 a month.

While carriers continue to stretch the meaning of "unlimited" — defined as "not limited or restricted in terms of number, quantity, or extent" — the recent interest in the concept has set off a fluid competition, as Verizon and AT&T attempt to slow market-share gains from the fast-growing T-Mobile, which kick-started the revival this summer, and fourth-place Sprint.

In this case, the lower entry price and mobile-hotspot data should make AT&T's unlimited offering a bit more competitive with its peers. It is still the most expensive of the bunch, however.