Non-Domestic Water and Wastewater – NEW August 2025

When operating a self-catering property in Scotland, a change in classification from domestic to non-domestic will affect how your property is treated for the purposes of Non-Domestic Rates (NDR) and Scottish Water services. This guidance outlines the implications of this transition, including how to engage with Licensed Providers and understand your responsibilities and charges. 

1. Non-Domestic Classification and Water Registration

Once your property meets the criteria to be classed as non-domestic self-catering accommodation, it will be entered onto the Valuation Roll by the local Assessor, independent of the local authority. This classification removes the property from Council Tax and places it on the Non-Domestic Rates register. 

Under NDR legislation, a self-catering property is classed as non-domestic if it is: 

• Available to let for at least 140 days per financial year, and 

• Actually let for 70 days or more per year. 

• Once added to the Valuation Roll, this change is shared with Scottish Water, triggering the non-domestic water and wastewater registration process. 

2. Communication from Scottish Water 

• Scottish Water will usually contact you by post at the property address. This initial letter will: 

• Notify you of a forthcoming site survey 

• Outline next steps and your responsibility to choose a Licensed Provider (e.g. Pure Utilities) 

• A second letter typically confirms which water services are present and prompts engagement with Licensed Providers to receive quotations for ongoing service. 

3. Role of the Assessor

The Scottish Assessors Association (SAA) determines whether a property is domestic or non-domestic based on use. The Assessor is independent from the local authority. If a property previously classed as domestic becomes a qualifying self-catering unit, the Assessor will: 

• Remove it from the Council Tax Valuation List 

• Add it to the Non-Domestic Valuation Roll 

• Assign a Rateable Value (RV) based on expected rental income as per guidance issued by the SAA’s Self-Catering Working Group 

This valuation is central to both your NDR liability and unmeasured water and drainage charges, where applicable. 

4. Water Services and Metering

During the site survey, Scottish Water will assess the property’s connection to the following services: 

• Water supply 

• Sewerage 

• Property drainage 

Not all properties are connected to all three. For example, rural properties may use septic tanks for wastewater, in which case only the water supply would be chargeable. 

Scottish Water is advised by regulators to install a meter wherever practical. If installed, metered water charges apply based on actual consumption. If metering is not feasible, unmeasured charges will apply based on Rateable Value. 

5. Charging Structure

Water and wastewater charges are regulated by the Water Industry Commission for Scotland (WICS). These charges represent the maximum allowed and are applied consistently by all Licensed Providers. 

• Metered properties pay per cubic metre (m³) used, plus a daily fixed charge. 

• Unmeasured properties pay based on the Rateable Value, multiplied by a regulated £/RV charge. 

• Property drainage is always charged based on Rateable Value, even if a water meter is installed. 

6. Choosing a Licensed Provider

If you do not actively select a provider, Scottish Water will assign one to your account. However, you retain the right to: 

• Switch to a different provider 

• Agree a fixed-term contract 

• Request support or a reassessment of charges if your property’s circumstances change 

A full list of Licensed Providers is available on the Scotland on Tap website. 

www.scotlandontap.gov.uk/suppliers/suppliers 

7. Key Considerations and Practical Advice

• Keep copies of all communications from Scottish Assessors, Scottish Water, and your Licensed Provider. 

• Notify the Assessor if your use changes (e.g. ceasing to let or converting to residential), as misclassification can lead to retrospective charges. 

Conclusion 

Understanding the implications of your property being classified as non-domestic is essential to ensuring correct billing and compliance. If you receive notice from the Assessor or Scottish Water, act promptly to engage with a Licensed Provider and review your service setup. 

Author of guidance: ASSC & Pure Utilities

Date of guidance:  August 2025

Website: www.assc.co.uk / www.pureutilities.co.uk 

Contact details: communications@assc.co.uk / callum.mccarthy@pureutilities.co.uk 

Disclaimer – Guidance Sheets are written by experienced Members of the ASSC and other experts. The information in the ‘Guidance Sheet’ is provided by the ASSC for use by Members in support of their own independent business decisions. It does not constitute advice or instruction for which the ASSC can be held liable in any way whatsoever. All Members and other readers remain responsible for the consequences of any decisions taken whether in the light of information gained from this Guidance Sheet or not.