Emergency Service Routing Digit (ESRD)


This numbering resource is fully administered by the CNA.

ESRD Description

511, 211, 311 and 811 NXX Codes are referred to as “ESRD Codes”. Consistent with Item 3.7 of the Canadian Central Office Code (NXX) Assignment Guidelines, ESRD Codes are unassignable as Central Office Codes. The line numbers within the ESRD Codes are intended for use as ESRDs for the purposes of providing wireless Enhanced 9-1-1 service in Canada. Specifically, ESRDs allow for the provision of cell site/sector location information to a Public Safety Answer Point (PSAP). Assignments are made in blocks of 100 consecutive 10-digit ESRDs (called ESRD Blocks) in the format NPA-N11-XXXX.


ESRD Assignment Guideline

The Canadian Emergency Service Routing Digit (ESRD) Block Assignment Guideline can be obtained from the CRTC website by clicking here.


ESRD Forms

The ESRD Application, Reservation, Information Change or Return form (Part 1) and Confirmation of ESRD Block(s) in Use (Part 3) forms are located in Appendix A of the Emergency Service Routing Digit (ESRD) Block Assignment Guideline, which is located on the CRTC website.

Those meeting the requirements to submit forms should extract the forms from the guideline for submission to the ESRD Block Administrator and submit them to NonCOCodeApps@cnac.ca.


ESRD Status

The currently assigned ESRD Blocks in Canada are listed here.


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