Conforming Meter List

The market rules require each metering installation used for IESO settlement purposes to be on the list of conforming meters established by the IESO. Meters on the conforming meter list are permitted to be used as the "main" or "alternate" meter, provided that all applicable conditions of acceptance are met.

Requirements to be on the conforming meter list

  • Market rules and the policies and standards established by the IESO, including the IESO standard Wholesale Revenue Metering Standard - Hardware, describe the accuracy and other requirements for meters and metering installations.
  • Sample tested by the IESO to verify that the meters are by design compatible with the IESO's metering communication facilities and software.

Metered market participants and metering service providers are solely responsible for ensuring that their metering installations comply in all respects with the applicable provisions of the market rules and of any policy or standard established by the IESO pursuant to the market rules. Meters shall be sealed by an accredited meter verifier and obtained from a manufacturer that has attained approval of type from Measurement Canada. 

Meters conforming to the requirements of the IESO market

Inclusion of a meter on the Conforming Meter List attached does not represent or warrant that any individual meter is accurate or complies fully with the requirements of the Market Rules or of any such policy or standard. The IESO reserves the right to:

  • Refuse registration of a metering installation in the event of non-compliance with the market rules or any such policy or standard.
  • Take such other action as may be permitted by the market rules in respect of a non-compliant metering installation even if the metering installation contains meters that are listed below.


Last updated: July 11, 2019

The following list specifies the first character of the internal identification number (device I.D.) assigned for each meter manufacturer. When programming meters, these conventions must be followed for all accepted meters on the conforming meter list.

Meter Manufacturer

Assigned Character

Elster Metering and ex-ABB


GE Canada Inc.


Schneider Electric/PML


Itron Canada, ex-SchlumbergerSema and ex-Schlumberger





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