T-Mobile is ready to throw free lines at (almost) everybody for the first time in 2021

According to a very well-connected inside source that's practically never wrong about these types of things, both new and existing T-Mo customers will once again be able to score gratis lines of wireless service starting tomorrow, March 17 without jumping through too many hoops or meeting all kinds of special conditions.

At first glance, the hot new offer, somewhat confusingly named "2021 Line On Us P6", may also look identical to the "2021 Buy One, Get One Voice Add a Line for Existing Customers" promo inaugurated less than a couple of weeks ago. But as the latter's fitting (albeit overlong) moniker suggests, there are a few key differences to note.

Because there is such a thing as too many (similar) deals, Magenta is reportedly gearing up to put an end to the BOGO (buy one get one) line offer today, essentially replacing it with the P6 Line On Us promotion instantly.

The main new eligibility requirement is having at least two paid lines on your T-Mobile account, in which case all you need to do is ask the "Un-carrier" for a complimentary third... or fourth, or fifth, or 12th voice line beginning March 17.

The beauty of these deals is their stackable nature, which means some of you may have reached an impressive number of free lines on your accounts without doing (or paying) much. If you paid enough attention to T-Mo's promotional periods last year, this could easily become your fifth line of service available at no monthly cost whatsoever.

As usual, a number of restrictions and limitations are set to apply here, the most notable of which partially excludes new customers opening their accounts by paying for two lines and existing owners of single line accounts looking to get a second paid line. If you're in one of those two situations, you'll need three paid lines to qualify for a fourth free of charge, which is certainly a little inconvenient but at least doesn't require everyone to buy a new line in order to get another one free.

While the full and detailed terms of the new deal are naturally still under wraps at the time of this writing, we pretty much know for sure already that those on Military, 55+, and First Responder accounts will be left out... yet again.

Another important limitation concerns rate plans that have hit their maximum number of allowed lines. That varies depending on the type of plan you're currently subscribed to, but for business users, who are not entirely excluded, the limit is set at 13 across the board.

Impressively, 2021's first free line promo for new and existing T-Mobile customers can also be combined with several other deals available right now, including Carrier Freedom, Keep and Switch, and Zero Cost to Switch in addition to all of last year's similar aforementioned offers.

After claiming yet another complimentary voice line, your savings will be applied to your account in the form of bill credits starting within two cycles from activation. To continue receiving said credits, you'll need to maintain the same number of voice lines on your account that were active at the time of your enrollment for one year. Afterwards, you will still have to keep at least two paid voice lines and the free new line active for T-Mo to keep the discount going.

All in all, it's quite simple to maximize your savings... once again, and never think twice about leaving Magenta for a "traditional" carrier like Verizon or AT&T that almost never offers this sort of straightforward discount with so few strings attached.