Reliance Jio portability from Other Networks

First up, you need to send a text message to your current operator requesting for a port out. The message PORT should be sent to 1900. In return, you will receive a Unique Porting Code from 1901 with 15 days validity from your current carrier.

Head to any Reliance Mobile Store or retailer and fill up the Customer Application Form (CAF) where you'll also fill in the porting code. Submit the required documents (proof of address, proof of identity and photograph), and in return Reliance will issue a new Reliance Jio SIM card. Once activated, this SIM will use the same phone number you already had, and your old SIM will be deactivated.
Source : MSN