What a cesspit is
A cesspit, also called a cesspool, is a sealed underground tank. It collects everything that leaves the property's drains and stores it. There is no outlet and no treatment. When the tank is full, a vacuum tanker pumps it out and takes the waste to a licensed treatment site.
That is the difference from a septic tank, which lets the settled liquid drain away into the ground and so needs emptying far less often. Our guide to what a cesspit is explains the difference in more detail.
Who can empty a cesspit
Sewage is controlled waste. It must be collected by a registered waste carrier, and you should be given a waste transfer note for each load. The firms that empty septic tanks use the same tankers for cesspits, so the companies on this register are the right place to start. Tell the firm it is a cesspit and how large it is when you ask for a price, because a cesspit usually holds much more than a septic tank and may need a larger tanker or more than one load.
This register lists 275 companies. 275 of them held an in-date Environment Agency waste carrier registration when we last checked the register on 06 March 2026. Each listing shows the registration number and its expiry date.
How often to empty
How quickly a cesspit fills depends on its capacity and on how much water the household uses. Building Regulations guidance for England (Approved Document H) says a new cesspool should hold at least 18,000 litres for two users, plus 6,800 litres for each extra user. Older tanks are often smaller and fill sooner.
- Check the level regularly, or fit a high-level alarm.
- Book the next empty before the tank is full. Letting a cesspit overflow or leak can be an offence, and it is a health risk.
- Ask about a regular schedule. Many firms offer one, and it avoids emergency call-outs.
What it costs
Firms price by volume, access and distance. Because a cesspit is emptied many times a year, the yearly cost is much higher than for a septic tank, so it is worth comparing at least two quotes and asking for the price per load. Our emptying cost guide gives typical prices by tank size.
Find a cesspit emptying firm near you
Pick your region to see the registered companies that cover it, or use the form at the top of the page and we will pass your request on.