T-Mobile is massively upping the promotional ante to drum up more sign ups to its network. T-Mobile's latest venture offers an additional line free for new or existing accounts having two or more lines.

According to T-Mobile's blog site, it wants to thank its loyal subscribers as well as attract new ones by offering enormous thanks by giving an additional line of service - for free. According to the blog, every T-Mobile customer with at least two active voice lines can avail of an additional third line without charge, after bill credits.

T-Mobiles Un-carrier promo also specified that it is their way to connect more of their family or more of their devices all the time. President and CEO John Legere said the extra line they are giving away free can be used by the subscriber in any way they choose. It is up to the customer's call whether they use the free line for wearables, tablet, or even turning their cars into a 4G LTE hotspot with SyncUp Drive.

To clarify, the Un-carrier offer carries two lines of T-Mobile ONE for $100. What this means is the customer gets an extra line without any additional charges, making the account have three lines within that same $100 a month with AutoPay inclusive of fees and taxes, according to Engadget. The previous offer in the same plan was $140 for the two plus one free, with this offer, the customer saves $40 from their monthly billing.

Accordingly, the offer applies to all who have existing T-Mobile ONE, Simple Choice and Simple Choice No Credit Plans, which covers most with two or more postpaid voice lines. The good news is, even small businesses with up to 11 lines can avail of the promo on their T-Mobile@Work account.

The offer commences on March 1. T-Mobile informs that the deal offer is only for a limited time, though no date pertaining to the end of sign-up for the promotion has been given as of yet. Additionally, T-Mobile also specified that the third free line is for customers to keep even after the promotional sign-up is over. The only condition is that the two principal accounts it is attached to remains active.

Meanwhile, T-Mobiles latest offer seems to clash head on with Verizon's latest unlimited data plan offer and just hours after AT&T offered 10GB of tethering data to its unlimited plan. The mobile wars seem to have re-ignited; it would now be a wait and see what response other carriers will give after T-Mobile's announcement.