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 – Current Release

CMOS 15 Release Notes


Error Codes -


CMOS Maintenance Schedule 2024-2025


CMOS Release Schedule 2024-2025


CMOS – Previous Release

Tariff Data Upload Guidance 2024 - 2025


CMOS 14.5 Release Notes


Error Codes - 14(5).0.1.0


Data Management

Data Assurance Service Glossary of Terms - May 2024


DQA guidance document - May 2024


Maximum number of transactions to be submitted into CMOS


Staff Data Protection Training Policy


Defect Management

ALM Observations (Defect Log)


CMOS Administration

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USR SPID/SC template

OPS Data Submission User Guide

OPS Data Submission Form Template

Tariff Timetable

Tariff Data Upload Guidance 2023-2024

MVI Batch Template

Guidance for Final meter read following Change of Use

SPID Flows Tradability

Recreating Supply Points Following Erroneous Deregistration

Non-Code Change (NCC) Request Guidance

NCC Change Request Template

FTP Reporting Login Instructions

Agreement Management (Wholesale) Guidance Note

MO Portal User Guide

CMOS, MO Portal and Bilaterals hub Access Proforma

CMOS Training Videos

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CMOS General Training

Reporting Overview

CMOS Training Documents

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CMOS 15.0 Retailer User Manual

CMOS 15.0 Wholesaler User Manual

Viewing and Creating Agreements in CMOS

Reporting Training Student Workbook

Reporting Training Presentation slides

Reporting Training Course Schedule

Remedy Service Management Interface

CMOS 3.0 Reporting User Manual

Content Outline Interface (Wholesale)

Content Outline Interface (Retail)

MOSL Guidance

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My MOSL Late Payment Guidance

My MOSL User Admin guidance

My MOSL - Gap Site Guidance

QMS Generic Queries User Guide

Submitting an General Query Request

MOSL Partner Account Guide

Submitting an Unplanned Settlement Run Request

Related pages

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 12.0 Release Note Final


CMOS 14 Release Note


Error Codes -


XSDs for CMOS Release 14.0


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