Mobile Number Portability
What is Mobile Number Portability?
Mobile number portability (MNP) enables mobile telephone users to retain their mobile telephone numbers when changing from one mobile network operator to another.
So if you are fed up of your mobile operator but still are not throwing away your sim card just because you don't want to change your mobile number. Using this Mobile Number Portability, you can choose from any tele operator of your choice and still keep the same old number.
How often can I switch my operator?
Once you switch your mobile number to a different tele operator, you can not switch your number again to another operator for the next 90 days. It means only one operator switch is allowed within any 3 month period.
So before switching you operator, be sure that you are going to stick to it for a minimum time of 3 months. It shouldn't be like that you saw an amazing one time offer and you switch to that operator blindly.
Restrictions and limitations
The only obvious restriction is that you can choose your desired operator from only within your current service area.
So if you are in Kolkata, you can only switch your operator within Kolkata itself. You can not choose some operator which is available in Delhi or Mumbai or Bangalore.