When a recipient receives a message from any provider or bank etc., a sender ID along with a prefix is displayed in the inbox. For example- VM-ICICIB, BW-Google, DM-Amazon, and VM-Redbus etc.
The prefixes VM, BW etc. are displayed because SMS is sent in huge numbers via bulk SMS. SMS providers follow rules framed by Telecom Regulatory Authority of India (TRAI) and according to TRAI rules,
| Operator | Code |
|---|---|
| Aircel, Dishnet Wireless | D |
| Airtel | A |
| BSNL | B |
| BPL Mobile/Loop Telecom | L |
| Idea Cellular | I |
| MTNL | M |
| Reliance Communications | R |
| Reliance Telecom | E |
| Tata Teleservices | T |
| Unitech | U |
| Vodafone Videocon | V H & Q |
The second character represents the location of the operator through which the message is received:
| Operator | Code |
|---|---|
| Andhra Pradesh | A |
| Assam | S |
| Bihar | B |
| Delhi | D |
| Gujarat | G |
| Haryana | H |
| Himachal Pradesh | I |
| Jammu & Kashmir | J |
| Karnataka | X |
| Kerala | L |
| Kolkata | K |
| Madhya Pradesh | Y |
| Maharashtra | Z |
| Mumbai | M |
| North East | N |
| Orissa | O |
| Punjab | P |
| Rajasthan | R |
| Tamilnadu | T |
| UP-East | E |
| UP-West | W |
| West Bengal | V |