CHENNAI: Bharti Airtel has launched a new tariff plan for its fixed line service. Priced at Rs. 549, the Airtel Dost Plan offers consumers free calls worth Rs. 2,500 a month for all local Airtel to Airtel mobile and landline calls. Additionally, customers can get Rs. 150 worth of free calls to other mobile and landlines. This is valid for both STD and local calls, says a release.