Sprint's Boost Mobile prepaid brand has extended several promotions that were originally due to end January 3. The 4 Lines of $50 Unlimited Gigs Plan for $100 offer has been extended until January 29. All lines must be new activations and at least one must be a port-in. Five lines are $125. Todo Mexico, which includes unlimited Mexican roaming, unlimited calls to Mexico and Canada and unlimited international text messaging, can be added all lines for $10 total. 4 Lines for $100 used to be available only at dealers but it's now listed on the Boost site separately from the in store only offers, so it might be available online or through telesales now. The following offers are listed by Boost as in-store only and are limited to participating dealers in selected markets. As always with store only deals, call the store first to verify availability and avoid disappointment. Add a Line, First Month Free add a new Unlimited Gigs line of service to an existing individual or family plan and get the first month of service for free. Extended until February 8. Bring Your Own Phone, Get Two Months Free Activation of a new line of service on the $50 Unlimited Gigs plan required. Extended until February 8. Buy One Phone Get One Free requires activation of a new line of service on the $50 unlimited plan. The offer is available to "new, port-in, or qualified upgrade Family Plan customers who have not upgraded in the last 120 days". The free phone must be of equal or lesser value than the purchased phone. Available for an unspecified limited time.