The service will be launched in metros and A category circles (Karnataka, Maharashtra, Tamil Nadu, Andhra Pradesh and Gujarat) on December 31 and in rest of the country by March 20, 2010.

Though TRAI had earlier fixed September 30 as the deadline to launch MNP, later it was extended to December 30 following a request from telecom companies.

The companies had also expressed reservations that once MNP is implemented, they might lose a significant number of high-value as well as post-paid customers.
But TRAI said it was a customer-friendly step meant to fuel competition among companies. MNP allows subscribers to retain their existing mobile number even after changing the service provider irrespective of the mobile technology.

MNP will be available only within a given licensed service area. If a BSNL customer in Bangalore changes the service provider, he cannot retain the same number if he moves to another city. Any subscriber is eligible to make a porting request any number of times but the change can be made only 90 days after the date of activation of the connection.