Septic Tank and Cesspool Emptying in England: Registered Waste Carriers, Desludging and Selling a Property
In England the company that empties a septic tank, small sewage treatment plant or cesspool must be a registered waste carrier; the Environment Agency says septic tanks and treatment plants should be desludged at least once a year, and a seller must tell the buyer in writing.
In this guide
In England, the sludge from a septic tank or small sewage treatment plant must be removed before it exceeds the tank’s maximum capacity, at least once a year or in line with the manufacturer’s instructions, by a registered waste carrier, and a cesspool must be emptied regularly, for example once a month, by a registered waste carrier.
Which systems the rules cover
Government guidance for England distinguishes three types of private sewage system. A septic tank is an underground tank where solids sink to the bottom and the liquid flows out and soaks through the ground. A small sewage treatment plant, also called a package treatment plant, treats the liquid so it is clean enough to go into the ground or a surface water. A cesspool is a tank that does not release sewage into the ground or a surface water. The “general binding rules” apply to septic tanks and small treatment plants that handle domestic sewage, and an operator who meets them does not need a permit. The guidance says the general binding rules do not apply to a cesspool, which has its own maintenance requirements. Wales, Scotland and Northern Ireland have separate arrangements, and this guide is limited to England.
Desludging a septic tank or treatment plant
The Environment Agency guidance on discharges to the ground says the operator must get the sludge that builds up in a septic tank or small treatment plant removed before it goes beyond the maximum capacity. It says this should be done at least once a year or in line with the manufacturer’s instructions. If the tank is not emptied often enough, solids are likely to be carried into the drainage field or soakaway, which can cause damage and pollution and lead to potentially expensive and disruptive repairs. The guidance page was last updated on 23 July 2026 and applies to England.
Emptying a cesspool
The separate guidance for cesspools says a cesspool must be maintained so that it is emptied regularly, for example once a month, by a registered waste carrier, and does not leak or overflow. It adds that the Environment Agency or the local council can require a cesspool in poor condition to be repaired or replaced, and that it is against the law for a cesspool to cause pollution. A cesspool does not need a permit unless the Environment Agency says otherwise. For a new cesspool, the guidance requires planning permission and building regulations approval and a minimum capacity of 18,000 litres for two users plus another 6,800 litres for each extra user. A system that releases sewage into the ground or a surface water is not a cesspool.
Why the emptying company must be a registered carrier
The guidance states that the company used to dispose of the waste sludge must be a registered waste carrier. An owner can check by asking the company to confirm this when arranging the emptying, or by asking the tanker driver for a copy of the company’s waste carrier certificate. This is the same requirement that applies to household and commercial rubbish removal, explained in our guides to waste carrier licences and checking a waste carrier. For how liquids are treated differently from ordinary rubbish, see our guide to liquid and trade effluent waste.
Selling or leaving a property
The guidance says that when selling a property, the seller must tell the new operator, meaning the owner or person responsible for the system, in writing that a sewage discharge is in place. The information to include is a description of the treatment and drainage systems, the location of the main parts and the discharge point, details of any changes made, how the system should be maintained together with the maintenance manual if there is one, and any maintenance records. Keeping emptying receipts and carrier details therefore has a practical use when the property is sold. If a system stops being used, the guidance says it must be decommissioned properly, removing anything that could cause pollution.
FAQs
How often should a septic tank be emptied in England?
The Environment Agency guidance says at least once a year or in line with the manufacturer’s instructions, and before the sludge exceeds the tank’s maximum capacity.
Who is allowed to empty a septic tank?
A registered waste carrier. The guidance says the owner can check by asking the company or the tanker driver for a copy of the waste carrier certificate.
How often must a cesspool be emptied?
The guidance says regularly, for example once a month, by a registered waste carrier.
Do I have to tell a buyer about my septic tank?
Yes. The guidance says a seller must tell the new operator in writing that a sewage discharge is in place, with details of the system and maintenance.
The bottom line
In England a septic tank, small sewage treatment plant or cesspool must be emptied by a registered waste carrier, with septic tanks and treatment plants desludged at least once a year or as the manufacturer says, and cesspools emptied regularly. Records of maintenance are useful when selling, because the seller must tell the buyer in writing about the system. This is general information for England, not advice on a specific system.
Sources
This guide draws on the following primary sources, current as of 24 September 2026:
- GOV.UK, “General binding rules: small sewage discharge to the ground” (Environment Agency, updated 23 July 2026)
- GOV.UK, “Septic tanks and sewage treatment plants: what you need to do: General binding rules”
- GOV.UK, “Septic tanks and sewage treatment plants: what you need to do: Your property has a cesspool”
Related guides
Waste carrier licences explained
How to check a waste carrier
Waste duty of care explained
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