Calling all T-Mobile customers! T-Mobile is offering an additional 3rd line for FREE via bill credits (limit 1 offer per account)! Existing customers will need to have a qualifying credit and be part of the Essentials, Magenta, or Magenta Plus plan to qualify. Credits may take up to 2 bill cycles and credits will stop if you cancel any lines. New customers will need to activate two voice lines to get the third free. Spread the word!