MLTS (Multi-Line Telephone System)

From NENA Knowledge Base

MLTS (Multi-Line Telephone System) is communications equipment comprised of common control unit(s), telephone sets, control hardware and software and adjunct systems used typically in enterprise settings such as hotels, government agencies, commercial offices, and campuses. Such equipment includes network and premises-based systems such as Centrex, VoIP, as well as PBX, Hybrid, and Key Telephone Systems (as classified by the FCC under Part 68 Requirements).

Related Terms:

Shared Residential MLTS (Multi-Line Telephone System) Service

The use of a specialized telephone system to provide service to residential facilities even if the service is not delineated for purposes of billing. Residential facilities shall be liberally construed to mean single family and multi-family facilities including Extended Care Facilities and Dormitories.

Relevant NENA Documents
Note: To find and download the document, copy the document number (like NENA-STA-010) from below and search the NENA Standards and Documents page.


  • NENA 03-502, Trunking for Private Switch 9-1-1 Service Technical Information Document (TID)
  • NENA 06-003, NENA Private Switch (PS) E-9-1-1 Database Standard
  • NENA 06-502, Industry Common Mechanisms for MLTS E9-1-1 Caller Location Discovery and Reporting Technical Information Documents (TID)

External References


FCC website: Multi-line Telephone Systems - Kari's Law and Ray Baum's Act