Certain extensions are reserved and cannot be assigned to users.
Currently, the reserved extensions are:
- 211 - Health and Human Services
- 311 - Government and non Emergency Information*
- 411 - Directory Assistance
- 511 - Traffic & Weather
- 711 - Telecommunication Relay Service
- 811 - Call Before You Dig
- 911 - Emergency services.
- 990-999 - Intermedia Unite services.
- 990 - Echo test number.
- 999 - Access to Conference Bridges.