Wholesale Tariff Simplification Sub-group

 Chair - James Lancaster (Thames Water)

Purpose

To investigate how to simplify the existing primary tariff structure in the non-household water market.

The Sub-group aims to impact the market by encouraging and enabling wholesalers to align their tariff structures to the best practice that is agreed collectively by market participants.

Success will be measured by the degree of wholesaler adherence to published Good Practice Guides as well as feedback from market participants, in particular Retailers and business customers.

Objectives/Outputs

  • Publish metered tariffs Good Practice Guide
  • Publish findings from Trade Effluent RFI
  • Publish Business Assessed and RV consultation

Assessed Charges consultation

On 24 March the sub-group issued a consutlation to seek industry views on options being considered by the sub-group in relation to simplifying and standardising wholesalers' assessed and unmetered (RV based) charges for non-household properties.

Read consultation document 

Submit consultation response

The consultation closes on Friday 25 April.

2025/26 wholesale price rises

In February 2025 the sub-group issued a request to wholesalers to provide retailers and their customers with more information on the 2025/26 wholesale price rises. You can find more information on this request below: 

Read communication request

Simplification and harmonisation of metered consumption bands Good Practice Guide

In February 2025 the sub-group published a good practice guide on metered tariff structures. This guide is a result of a phased consultation in 2023 that sought feedback on several options on metered tariff structures. Following refinement of the preferred options, the sub-group recommends that volumetric consumption bands are aligned to a 'Tariff basket structure' with set thresholds, commencing from 1 April 2026.

Read Good Practice Guide

As set out in the Good Practice Guide, the phased implementation of the recommended metered tariff structure should be completed by the start of the 2030/31 charging year. To assist with commencing the phased implementation from the 2026/27 charging year, CMOS now has the ability to future date tariff transactions, a change introduced in the December 2024 CMOS release.

Meetings

Title Date Time Location Agenda Minutes Papers Slidepack Misc
RWG Tariff webinar 20/04/2023 3:00 pm - 4:00 pm Microsoft Teams RWG Tariff Consultation
RWG subgroup - Tariff 19/01/2023 3:00 pm - 4:00 pm MS Teams Download
RWG subgroup - Tariff 08/12/2022 MS Teams Download
RWG subgroup - Tariff 27/10/2022 MS Teams Download Download
RWG subgroup - Tariff 06/10/2022 MS Teams Download
RWG subgroup - Tariff 15/09/2022 MS Teams Download
RWG subgroup - Tariff 12/05/2022 MS Teams Download Download
RWG subgroup - Tariff 21/04/2022 MS Teams Download
RWG subgroup - Tariff 31/03/2022 MS Teams
RWG subgroup - Tariff 10/03/2022 MS Teams
RWG subgroup - Tariff 17/02/2022 MS Teams
RWG subgroup - Tariff 27/01/2022 MS Teams Download
RWG subgroup - Tariff 06/01/2022 MS Teams Download
RWG subgroup - Tariff 16/12/2021 MS Teams
RWG subgroup - Tariff 04/11/2021 MS Teams Download
RWG subgroup - Tariff 14/10/2021
RWG subgroup - Tariff 23/09/2021 Download
RWG subgroup - Trade Effluent Tariff 20/09/2021
RWG subgroup - Tariff 02/09/2021 Download Download Download Download
RWG subgroup - Trade Effluent Tariff 30/08/2021
RWG subgroup - Tariff 12/08/2021
RWG subgroup - Trade Effluent Tariff 09/08/2021
RWG subgroup - Tariff 22/07/2021
RWG subgroup - Trade Effluent Tariff 19/07/2021
RWG subgroup - Tariff 01/07/2021
RWG subgroup - Trade Effluent Tariff 28/06/2021
RWG subgroup - Tariff 10/06/2021 Download

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