The Central Market Operating System (CMOS) is the core IT system for the non-household market. CMOS manages all the electronic transactions involved in switching customers and provides water usage and settlement data. MOSL, in partnership with CGI, are continually working to improve CMOS operations. Here you’ll find MOSL’s release plans, outlining future functionality.

CMOS – Next Release

CMOS Maintenance Schedule 2022

Error Codes

CMOS 11 Release Notes

CMOS – Current Release

Release Schedule 2021-2022

Error Codes

CMOS 10.0 Release Notes 1.22

XSD Updates for CMOS Release 10.0

CMOS – Previous Release

CMOS 9.0 Release Note 1.16

Data Management

Maximum number of transactions to be submitted into CMOS

Staff Data Protection Training Policy

Security Incidents and Breaches Policy

Defect Management

Workaround Log

ALM Observations (Defect Log)

CMOS Administration

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CMOS, MO Portal and Bilaterals hub Access Proforma

FTP automated reports folder structure

ITSM Browser Settings - Recommendations

MO Portal User Guide



MVI Template

CMOS Training Videos

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CMOS General Training - Wholesaler

CMOS General Training - Retailer


CMOS General Overview

Tariff Maintenance

Agreement Management & Historical Data

TCORRs, Meter Networks & Non-Market Meters

Reporting Overview

Remedy Service Management Interface

CMOS Training Documents

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Session 1 Administration training slides

Session 2 CMOS General Overview training slides

Session 3 Register SPID (Wholesaler) training slides

Session 4 Register SPID (Retailer) training slides

Session 5 Maintaining Market Data (Wholesaler) training slides

Session 6 Maintaining Market Data (Retailer) training slides

Session 7 Meters Meter Reading (Wholesaler) training slides

Session 8 Meters & Meter Reading (Retailer) training slides

Session 9 Registration Transfers (Retailer) training slides

Session 10 Tariff Maintenance (Wholesaler) training slides

Agreement Management and Historical Data training slides

CMOS 3.0 Reporting User Manual

CMOS 10.0 Retailer User Manual

CMOS 10.0 Wholesaler User Manual

Interface Training (Retail) slides

Interface Training (Wholesale) slides

Remedy Service Management Interface

Reporting Overview training slides

Tariffs Full (Wholesaler) training slides

TCORRs, Meter Networks & Non-Market Meters

Reporting Training Course Schedule

Reporting Training Presentation slides

Reporting Training Student Workbook

MOSL Guidance

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Agreement Management (Wholesale) Guidance Note

CMOS Privacy Notice Policy

FTP Reporting Login Instructions

NCC Change Request Template

Non-Code Change (NCC) Request Guidance

Recreating Supply Points Following Erroneous Deregistration

SPID Flows Tradability

Viewing and Creating Agreements in CMOS

Using PowerBI Dashboards

Tariff Data Upload Guidance 2022-2023

Guidance for Final meter read following Change of Use

Non-code change requests

View CMOS-impacting change requests here.

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Operations and Release Working Group (ORWG)

The latest outputs from the ORWG.

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CMOS – Release archive

CMOS 9.0 Release Note 1.16

CMOS 8.5 Release Note 1.14

CMOS 8.0 Release Note 1.10

CMOS 7.0 Release Note 2.1

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