We are dedicated to helping the retailers who provide account services to businesses in our supply area.

Rob, Jules and Andrea

Wholesale Service Desk

Retailers and COVID-19

Following MOSL’s recent code changes aimed at stabilising the retail market for non-household (NHH) customers, we want to ensure our retailers are applying these changes consistently and fairly. We also want to assure you that we are monitoring Government updates and guidance regarding COVID-19 and are responding accordingly.

On 30 March two temporary code changes were implemented that look to address two specific issues that have recently emerged from the COVID-19 pandemic. Firstly, the impact of the Government lockdown on a range of business premises that have had to close and secondly the impact on cash flows through the NHH retail market due to some businesses’ inability to pay their bills in full. 

  • We would like to remind retailers of the requirements set-out by MOSL to ensure that the changes they are making to CMOS under code change CPW091 are carried out specifically and solely as a result of the lockdown measures. Only businesses that have temporarily closed down due to COVID-19 from 20 March are to be included under this change, and evidence is required to be provided demonstrating that this is the case. 
  • The second code change, CPW093, provides retailers with the ability to defer payments to wholesalers by up to 50% for up to three months. We want to remind retailers that if they are in a position to pay more than 50% of wholesaler charges, both MOSL and Ofwat expects them to do so. Retailers should not automatically default to 50% deferral of wholesaler charges. 

Latest update

Our top priority remains the health of our workforce and ensuring we are able to continue to provide a resilient supply of high quality water to our customers – we would appreciate your assistance with this. 

We will continue to have a limited number of employees in the office and in the field to ensure we can maintain adequate social distancing, in line with the Government’s latest advice. While the safety of our employees and customers is our first priority, our Wholesale Service Desk and operational teams are dedicated to providing the best possible service in the circumstances.  

We appreciate your ongoing patience.

If you have any questions we are contactable Monday to Thursday from 8am to 5pm and on Friday from 8am to 4:30pm on 0203 968 9805 or

Information for businesses reopening

Water UK has provided guidance to businesses that have been closed or running on reduced staff about their water supply.

Below is a summary of the Water UK advice for unoccupied buildings, where water has not been in use for many weeks which may now be subject to stagnation:

  • Run all taps to flush water through 
  • Remove aeration devices e.g. shower heads, before flushing
  • Follow manufacturers' advice for all appliances – including internal filters or water softeners
  • Make sure plumbers are approved under the WaterSafe scheme   

Visit the Water UK website for more details, however if you have any concerns please contact us.    

Open Water

Most businesses in England have been able to choose which company (known as a retailer) supplies their water services such as account management, billing and customer service, since 2017. 

If you were a SES Water business customer and have not switched your retail service provider you will now be served by SES Business Water. Details about how to contact your retailer can be found on the Open Water website.

Open Water website

Do we supply your water?

To find out if we are your water supplier simply enter your business postcode

We have a Wholesale Service Desk dedicated to liaising with retailers. We aim to deliver excellent customer service to both business customers and retailers and will manage the communication of planned and unplanned work to ensure retailers are kept informed.

Our team also supports retailers to establish contracts and offer ongoing support throughout the contract period. They offer advice on internal processes, conducting periodic performance reviews, escalating issues when required and recommending improvement initiatives. The team can also advise on the additional services we offer such as meter reading or obtaining meter data from loggers. 

Charges and billing

All charges, both primary and non-primary, are published in our Wholesale Charges document. This includes charge rates and any specific conditions associated with our service. Invoicing for water supplied will be in accordance with the market settlement reports which are based on our wholesale charges. Invoice queries should be directed to the contact shown on the invoice. Escalations of invoice queries will be handled by the account manager.


Please use the retailer forms available on the MOSL website.

Retailer forms

Contact us

The Wholesale Service Desk is available Monday to Thursday from 8am to 5pm and on Friday from 8am to 4:30pm. 

Call 0203 968 9805 during working hours and use 01737 772000 for emergency issues.

Useful information

Loss of profit claims