Sometime we have a thought that we cant go to another network because the number we are using is having with so many people as a contact of mine. So if we are changing network then the number will also change and we will miss from so many peoples contacts list. But its totally wrong. There is option known as Mobile nUmber Portability (MNP). With MNP we can go to any network of our choice without changing our current number.
Lets discuss what is MNP is and how its worked? MNP is a process by TRAI which helps us to leave a network and join another at our own choice. All mobile number have a special code names as Unique Porting Code. We can get this code from the current network and have to give this to the new network retailer to whom we want to join. After this the new network operator will give you a form to fill with the documentation. After filling the form the retailer will give you a new sim card and a time period of at most 7 Days. In these 7 days when ever your old SIM shows you a no network message or out of service message then you have to through the old card and have to insert the new one. Basically the new card take at most 2 hours to activated after the old sim card get deactivated. Then you can enjoy all the new operator benefits with network with the same old number. But keep in mind that the old network Balance or anything will not come to the new network only besides your number. To get your Unique Porting Code you have to send a sms to a number which will cost you around Rs.1 from main balance. Some networks also give you to send it for free. sms PORT <number> to 1900. Suddenly you will get a sms with your code. This code will valid for only 15 days from the date of the sms sent. In this period you have to go to the new operator retailer or store to fill all the documental processes.