Guide
Sewage treatment plant cost: what UK sellers publish for the unit
Updated
Sewage treatment plant cost, for the unit alone, is a median £2,196 ex VAT for a 6 person plant across the three UK sellers that publish one on their own page, read 28 October 2026. A 9 person plant runs £2,308.20 to £4,756, and the smallest domestic plant starts from £1,430 + VAT.
Published unit prices
| Seller | Plant | Published price |
|---|---|---|
| WTE (manufacturer) | its smallest domestic plant | from £1,430 + VAT |
| JD Pipes | 6 person | £2,061.89 ex VAT |
| Tanks Direct | Klargester 6 person | £2,196 ex VAT |
| Fuel Tank Shop | Klargester BioTec+ 6 person | from £2,196 |
| JD Pipes | 9 person | £2,308.20 ex VAT |
| Fuel Tank Shop | Klargester BioDisc BX, 9 person | from £4,756 |
Source: UK Sewage Treatment Plant Price Index: every row, with its source
What the unit price leaves out
- Delivery and offloading, which some sellers price on top.
- Commissioning, which a technician carries out once the plant is in.
- The installation itself: excavation, the electricity supply the plant runs on, the drainage field or outfall, and reinstating the ground.
- Building regulations: Approved Document H sets the standard for a treatment plant, its siting and its drainage.
Approved Document H sets the building regulations standard for a treatment plant, where it may be sited and how its drainage works.