# Number Porting
> The process of transferring an existing phone number from one service provider to another

Number porting lets subscribers keep their phone number when switching VoIP providers.

## What is number porting?
Number porting (also called Local Number Portability or LNP) is the process of transferring an existing telephone number from one service provider to another. It allows businesses and consumers to switch carriers without changing their phone number.

## Porting in VoIP migrations
When organizations migrate from traditional telephony to [VoIP](/voip-glossary/voip/), number porting ensures continuity. The process typically involves submitting a Letter of Authorization (LOA) to the new provider and waiting for the port to complete — usually within a few business days.

## Related Terms
- [DID](/voip-glossary/did/)
- [SIP](/voip-glossary/sip/)