Every night across the UK thousands of commercial kitchens finish service, look at a fryer full of used cooking oil, and make the same decision. They pour it down the drain.
It is quick. It is easy. And it is a criminal offence.
If you run a food business in the UK — a fish and chip shop, a takeaway, a kebab shop, a pub kitchen, a café — this article is for you. Because what happens to your used cooking oil at end of service is not just an operational inconvenience. It is a legal matter with serious consequences for your business.
What does the law actually say?
Under Section 111 of the Water Industry Act 1991 it is a criminal offence to discharge any matter into the public sewer that is likely to injure the sewer, interfere with the free flow of its contents, or prejudicially affect the treatment of sewage. Fat, oil and grease — collectively known as FOG — falls directly within this definition.
This is not a grey area. There is no minimum volume below which it becomes acceptable. There is no exception for small businesses. If your kitchen is pouring used cooking oil down the drain it is breaking the law. Full stop.
The Food Safety Act 1990 adds a further layer of legal responsibility. Food premises are required to maintain their drainage in a clean and functional condition. An Environmental Health officer who discovers evidence of improper oil disposal during a routine inspection can issue an improvement notice on the spot. Continued non-compliance can result in a prohibition order — which means your kitchen is legally required to stop trading until the issue is resolved.
What actually happens to the oil?
When cooking oil enters the sewer system it cools, solidifies and sticks to the inside of pipes. Over time — combined with wet wipes, food waste and other materials — it builds into what are known as fatbergs. The UK recorded over 370,000 sewer blockages in a single year caused by fat, oil and grease from commercial and domestic kitchens. The annual cost of clearing these blockages to the UK taxpayer and water companies is approximately £100 million.
Fatbergs are not just an environmental problem. They back up sewers, cause flooding in streets and properties, and cost enormous amounts of money and time to remove. The largest fatberg ever discovered in the UK weighed 130 tonnes and was found under Whitechapel in London. It took nine weeks to remove.
Your kitchen contributes to this problem every time oil goes down the drain. And water companies are getting increasingly serious about identifying and prosecuting the businesses responsible.
Are Environmental Health officers actually enforcing this?
Yes — and increasingly so. Environmental Health officers across the UK are actively targeting food businesses for improper oil disposal as part of wider campaigns around drainage, hygiene and food safety compliance. Enforcement action has increased significantly in recent years as local authorities come under pressure from water companies and central government to tackle the fatberg crisis.
The consequences of an enforcement visit are not limited to a fine. An improvement notice requires you to demonstrate compliance within a set timeframe — usually 14 days. Failure to comply results in prosecution. A prohibition order can close your kitchen immediately. And once you are on the Environmental Health radar you can expect follow-up visits.
What are food businesses supposed to do instead?
There are three legally compliant methods for disposing of used cooking oil from a commercial kitchen.
The first is licensed waste oil collection. A registered carrier visits your premises on a scheduled basis and collects stored oil in drums for processing into biodiesel. This works well for high-volume operations — busy chippies, large restaurant groups, hotel kitchens — that generate enough oil to make collection economically viable for the collector. For smaller operations that generate lower volumes most collectors will not service them, or will charge a collection fee that makes the economics unworkable.
The second is a grease trap. A physical device installed in your drainage system that captures fat, oil and grease before it enters the sewer. Grease traps work but they have significant drawbacks — installation costs between £300 and £5,000 depending on the size and complexity of the installation, and they require regular specialist maintenance and cleaning. For a small independent food business these costs can be prohibitive.
The third is solidification and trade waste disposal. A product like Fry Block converts liquid cooking oil into a solid block that can be placed directly in your normal trade waste bin. No installation. No contractor. No collection schedule. No paperwork. The solid block is not classified as hazardous waste and requires no specialist disposal — it goes in your trade bin alongside other solid kitchen waste.
How Fry Block solves this problem
Fry Block is a plant-based powder that turns used cooking oil completely solid in under an hour. At end of service you sprinkle the powder into your hot oil, stir for 30 seconds, and leave it to cool. By the time you have finished your end-of-service clean the oil is a firm solid block. You lift it out, bag it, and put it in your trade waste bin.
That is the entire process. Two minutes of your time. Legally compliant. No equipment, no installation, no contractor, no paperwork.
Fry Block costs from £27 per month delivered to your kitchen door. For a kitchen that changes oil twice a week that works out at less than £1.40 per oil change — less than the cost of a cup of coffee.
The fine for a single Environmental Health enforcement action costs more than two years of Fry Block.
The bottom line
If your kitchen is pouring used cooking oil down the drain, you are breaking the law. The risk is real, the enforcement is increasing, and the solution is simpler and cheaper than most food business owners realise.
You do not need a grease trap. You do not need a collection contract. You need a pouch of Fry Block powder and two minutes at end of service.
Request your free 200g trade sample at fryblock.co.uk — enough for two full fryer treatments at no cost, posted to your kitchen within two working days.