Trade effluent charges

The Commission for Regulation of Utilities (CRU) published a decision on updated non-domestic and trade effluent tariffs on 08 July 2026. For licensed trade effluent customers, this means a new set of national trade effluent charges will come into effect starting on 1st October 2026.

The CRU has also published its final decision on trade effluent transition arrangements that will support customers when the new trade effluent charges come into effect, along with rules that will ensure consistent and accurate billing.

Up to 1^st October 2026, the charging arrangements for trade effluent customers have been varied depending on the location and type of customer. These legacy arrangements have resulted in a wide range of separate trade effluent charges based on level, structure and application across the country. Many of the legacy arrangements have weak incentives to reduce the level of pollutants and the total volume of trade effluent being discharged into Uisce Éireann’s wastewater network.

The new trade effluent charges will only apply to licensed customers who discharge trade effluent into Uisce Éireann’s wastewater network. The new trade effluent charging arrangements will become effective on 1st October 2026. 

The CRU’s decision provides for the integration of harmonised national trade effluent charging arrangements into the overall Non-Domestic Tariff Framework. As part of the CRU decision made on 08 July 2026, the new trade effluent tariffs have been agreed and will become effective on 01 October 2026. Uisce Éireann will maintain the existing Local Authority (LA) trade effluent charging arrangements until this date.

The CRU decision means trade effluent customers will be classified into three trade effluent tariff categories for charging purposes, based upon their primary business activity and their annual water consumption. A customer’s classification will be reviewed annually based on the most recent, if any, changes to the business activity and the most recent water consumption data.

Uisce Éireann will assign a business activity to a connection as either Commercial or Industrial. We shall do so by assigning a unique code (referred to as a TEC Code) based on an extensive business activity description list. The TEC code reflects each customers primary activity and relative strength of the trade effluent discharged.

If you are unsure of what broad business activity (“Industrial” or “Commercial”) is most applicable to your trade effluent connection, please contact us at dischargetosewer@water.ie.

Along with the business activity, annual consumption (m³) or Annual Quantity (AQ) is the next factor used to assign a trade effluent connection its tariff category. The tariffs to apply will be determined based on the connection’s previous year’s annual water consumption.

Correspondence will be issued to all trade effluent customers annually advising of their AQ, business activity and the Trade Effluent Tariff Category that will be applied at the start of each new tariff year (starting on 1st October). For further information, visit the AQ page.

Customers may query their assigned AQ or business activity if they feel it does not accurately represent their business and places them in wrong trade effluent tariff category. The ability to query shall only become available during August 2026, when each TE customer has been advised of their tariff category.

Multi-part charges apply for each metered trade effluent tariff class comprising the following fixed and variable components:

1. Standing Charge - Commensurate with the Annual Quantity of water supplied (or trade effluent discharged in the case of a wastewater only connection); and
2. Licensing and Compliance Charge – Applied on a per-license basis; and
3. Variable Charge - Reflecting the volume of trade effluent discharged. For any trade effluent category 1 customers, then a volumetric rate applies commensurate with the Annual Quantity of water supplied (or trade effluent discharged in the case of a Wastewater only connection). For trade effluent Category 2 and 3 customers, then a Mogden formula charge will be applied.

For unmetered trade effluent customers, then tariffs will be comprised of the following fixed components:

• Single, Fixed Charge Per Annum - for trade effluent unmetered connections; and
• Licensing and Compliance Charge - applied on a per-licence basis.

For further information on the Mogden formula charge visit the Customer Information Paper, trade effluent FAQs and the trade effluent calculator – access to these supports are provided at the end of this webpage.

Yes - Following a publication consultation process, the CRU has also published its final decision on trade effluent transition arrangements that will support customers once the trade effluent charges are effective.

Trade effluent customers are eligible for bill capping arrangements from the 1st October 2026 if they are moving tariff structure For example, moving from a Local Authority trade effluent charge to the new national Mogden charge.

Eligible trade effluent connections will qualify for a cap (if required) on their bill if the change in their bill over the 2026 Tariff Year (between 1st October 2026 to 30th September 2027) is calculated to be greater than or equal to a €750 increase because of the updated Non-Domestic Tariff Framework.

The annual cap is calculated as a percentage of the cost reflective bill (rather than current bill). The level of the cap in year 1 will be 9.4%.

The annual cap is calculated as a percentage of the cost reflective bill, rather than current bill. The level of the cap in year 1 will be 9.4%, where a cap will only be applied to a trade effluent customer’s bill where it is of benefit.You can read more about the June 2026 Trade Effluent Tariff Framework CRU final decision and response paper on the CRU website. Worked examples can be found in UÉ’s customer information paper and the trade effluent tariff calculator – links can be found in the customer support section at the end of this page.

The CRU has approved two rules to support the consistent and equitable application of trade effluent charges:

i. Representative sampling required for Mogden formula charges

A Mogden formula charge depends on both the volume and strength of the trade effluent discharged. The Mogden Formula therefore requires representative sampling and analysis of the Trade Effluent discharged from a premises in order to derive the inputs required to calculate the charge.

Uisce Éireann carries out regular sampling and analysis of trade effluent discharges to determine a representative average of COD and SS pollutant strength parameter values necessary to determine accurate Mogden Formula charges.

Uisce Éireann will use representative sampling data where available when setting Mogden Formula charges. In cases where representative sampling data is not available (for example, for a new connection to UÉ’s network), the values for Chemical Oxygen Demand (COD) and Suspended Solids (SS) will be estimated by reference to the emission limits set out in the customer’s trade effluent licence.

In such cases, 30% of the applicable Emission Limit Values will be used to derive estimated COD and SS values for the purposes of applying a Mogden formula charge. These estimated values may only be used in limited circumstances and for no more than one tariff year, after which representative sampling data must be in place.

ii. Sanitary Wastewater allowance

A trade effluent customer’s discharge will typically include both trade effluent arising from business activities and sanitary wastewater arising from on-site personnel. In circumstances where the sanitary wastewater component of a trade effluent customer’s discharge cannot be separately measured, or where representative sampling of trade effluent excludes sanitary wastewater, Uisce Éireann will apply a standard allowance to estimate the sanitary wastewater volume for billing purposes.

This allowance is based on a standard “litres per working day” approach and reflects typical domestic-type wastewater generated by personnel on site. The following default allowances will apply:

• 25 litres per head per working day, where there is no canteen on the premises serving hot meals; or
• 50 litres per head per working day, where there is a canteen on the premises serving hot meals.

For the purposes of this calculation, a working day shall be defined as an eight-hour shift. The sanitary wastewater allowance will therefore be calculated as follows:

Sanitary wastewater allowance (m³ per year) = x litres per 8-hour shift × total employee hours worked on site per year ÷ 8

Where:

• x = 25 litres, increasing to 50 litres where the premises includes a canteen serving hot meals; and
• total employee hours worked on site includes all personnel present on site, including permanent staff, seasonal staff, temporary workers, contractors and any other personnel.

All wastewater discharged by a trade effluent connection, including any sanitary wastewater, will be treated as part of the trade effluent discharge for billing purposes. The sanitary wastewater allowance volume will be charged at the applicable volumetric rate commensurate with the trade effluent customer’s tariff band.

The inclusion of trade effluent service charges in the overall Non-Domestic Charging Framework delivers:

• Charges that are simpler and more transparent than what exists today
• Charges that are more equitable by ensuring that commercial customers discharging the same volume of trade effluent are charged the same and industrial customers discharging the same volume and strength of trade effluent are also charged the same
• Charges that reflect the actual costs of providing trade effluent services to the business sector
• Charges that promote water conservation by maintaining a relatively low fixed standing charges, providing more scope and incentive for customers to reduce their water and wastewater bills
• Charges that align with the polluter pays principle, that is, customers discharging high-strength trade effluent pay higher charges than customers discharging low-strength trade effluent (for the same volume of trade effluent discharged).

Customer Supports

Download our 2026 Customer Information Paper which summarises the CRU’s decision, considers overall customer impact and includes case study examples of the new charges including the application of the Mogden Formula (see section 4). For information on our non-domestic water and wastewater tariff rates effective from 01 October 2026 please visit Business Charges webpage.

• Download the Water Charges Plan from our Customer Commitment page, sets out all of Uisce Éireann's changes.

Uisce Éireann is pleased to offer an Advanced Water Stewardship Programme in partnership with Water Stewardship Ireland and the Sustainable Enterprise Skillnet. This new offering is designed to support business customers in addressing trade effluent and water quality challenges. It also helps participants prepare for upcoming regulatory changes and develop strategies to manage trade effluent charges effectively.

Learn more about the Advanced Water Stewardship.

Uisce Éireann has created four sector specific documents to support customers as they navigate the new trade effluent charging arrangements.

These four sectors include:

• Brewing
• Food Processing
• Manufacturing and Engineering
• Biopharma and Chemical

For more information on other Business Customer initiatives on water conservation, testimonies and signposting to available external funding options to improve environmental performance, please see our Water conservation for business page.

UÉ has published an online Trade Effluent (TE) Tariff Calculator to assist customers in understanding the new TE charging framework and to provide an idea of what the new charges could potentially mean for customers for the tariff year commencing on 01 October 2026.