T-Mobile today kicked off its latest free line promotion.

For a limited time, T-Mobile customers can get a free voice line added to their account. It doesn’t look like T-Mo is advertising this deal on its website, but the carrier confirmed to TmoNews that the offer is now available.

This free line deal is open to new customers who add two voice lines on an eligible rate plan as well as existing customers who have at least two paid voice lines on a qualifying rate plan. After you activate your new line, it’ll be covered by monthly bill credits.

The rate plans that are eligible for this free line deal include Magenta, Magenta Plus, Business Unlimited, T-Mobile One, T-Mobile One Plus, Essentials, and Simple Choice.

T-Mo also confirmed to me that this offer is stackable with current device offers as well as past free line offers.

Several T-Mobile customers over on Reddit say that they’ve been able take advantage of this deal using chat inside the T-Mo app, over 611, and other methods. So if adding a free voice line to your account is something you’d like to do, you should contact T-Mobile soon and ask about taking advantage of this deal. Let us know if you do get it added to your account!

Thanks kmetz!