An internal T-Mobile document obtained by The Mobile Report suggests that the carrier will be offering a special holiday deal on home internet service powered by T-Mobile's 5G service. Customers who already have one or more postpaid lines can add a line of unlimited 5G home internet service for only $30 per month. This is achieved by giving the customer a $30 per month invoice credit. But be aware that you must have autopay enabled on your account to snag this special deal.