Food waste in contract catering: thresholds and duties

A catering operation can compost its food waste on site as long as it serves fewer than 130 covers a day over a working year, around 260 with two composters, and roughly 200 and 400 on a school calendar of 140 days. Above 3,000 kg a year, on-site composting is no longer the right answer. It all comes down to one multiplication: 75 g of food waste per meal served, of which around 70% actually reaches the composter. This page works through the calculation, the thresholds per day of service, the kitchen constraints and the regulatory framework.

How much food waste a catering operation produces

The starting point fits in one figure: 0.075 kg of food waste per meal served. That ratio covers peelings and preparation trimmings, production losses, plate returns and coffee grounds. It comes from ADEME ratios (France) cross-checked against readings from the sites we have equipped, and it is the one our online sizing tool applies. The detail by sector, including the difference between primary (0.070 kg) and secondary schools (0.100 kg), is in the guide to sizing a composter.

A second coefficient changes everything, and it is almost always forgotten: the capture rate. Part of the theoretical volume never reaches the composter, because some diners eat elsewhere, because separation is never perfect, because services are skipped. We use 70%. It is that captured volume which sizes the equipment and sets how often it has to be emptied: sizing on the theoretical figure means installing one composter too many.

Those 1,040 kg come in under the 1,500 kg mark: a single ABC composter is enough, and it will need emptying a handful of times a year rather than every week.

How many covers on-site composting can follow

The question that decides is not "how much room do you have?" but "how many covers do you serve?". The table applies the ratio and the capture rate to a staff catering operation open 220 days a year, with no commercial rounding.

Sizing for a catering operation open 220 days a year. Ratio 0.075 kg per meal, capture rate 70%.

Covers a day	Volumes captured	Composters	Collections a year	Monthly, excl. VAT
40	462 kg	1	3	109 €
60	693 kg	1	4	119 €
80	924 kg	1	9	169 €
100	1,155 kg	1	12	199 €
150	1,733 kg	2	6	278 €
200	2,310 kg	2	12	398 €
250	2,888 kg	2	12	398 €
260 and above	more than 3,000 kg	outside the scope of on-site composting

Three readings of this table are worth keeping. The first: what triggers a second composter is a tonnage, 1,500 kg captured, not a number of covers; translated into covers, that threshold falls at around 130 a day over 220 days of service, and around 200 on a school calendar. The second: between two thresholds, serving more covers changes nothing, going from 200 to 250 covers a day stays on the same equipment. The third: above 259 covers a day over 220 days, the honest answer is no longer on-site composting. What takes over is set out in the comparison of anaerobic digestion or on-site composting.

Staff restaurant or school kitchen

For the same number of covers, a staff restaurant and a school kitchen are not sized the same way, because the calendar differs: around 220 days of service on one side, around 140 on the other. At an equal ratio, the school kitchen therefore produces markedly less over the year and can take far more covers a day.

What separates a staff restaurant from a school kitchen, from the point of view of on-site composting. The covers absorbed are calculated at a ratio of 0.075 kg per meal and a 70% capture rate, as in the sizing tool.

Criterion	Staff restaurant	School kitchen
Days of service	around 220 a year	around 140 a year
Seasonality	quiet in August and late December	a full two-month stop over the summer
Covers absorbed by one composter	up to 129 a day	up to 204 a day
Covers absorbed by two composters	up to 259 a day	up to 408 a day
Who makes the sorting decision	the adult diner, when clearing the tray	the pupil, supervised by service staff
Point to watch	holding the instruction despite turnover	reinstating the instruction every new term

A school kitchen serving 150 covers over 140 days produces 1,103 kg captured: a single composter. The same 150 covers in a staff restaurant open 220 days produce 1,733 kg, so two composters.

One clarification on the ratio, because it moves the result: the “school” column above applies the 0.075 kg used by the online quote. Using the finer ratios noted earlier, 0.070 kg in primary and 0.100 kg in secondary schools, the thresholds become 218 and 437 covers in a primary school, 153 and 306 in a secondary. The same kitchen serving 150 covers, calculated at 0.100 kg, produces 1,470 kg: still a single composter, but 12 collections and 199 € excl. VAT a month on the French grid. If in doubt, take the higher ratio for your case and weigh from the first year.

The summer break is not a technical problem: a composter that receives nothing for eight weeks finishes maturing, and the first emptying of the new term takes away a mature material. It only means timing removals around term dates. The delicate point is elsewhere: the sorting instruction is lost every new term and has to be reinstated, something university and business school campuses experience on a larger scale. For a public body, the public sector and education page sets out the whole arrangement.

Separation in the kitchen and food safety constraints

A catering kitchen works on a linear flow: nothing dirty comes back towards the clean side. That objection is settled by where the machine goes. The composter does not come into the kitchen: it is installed outside, on around 1 m² of flat, load-bearing ground, away from food handling areas. It does not plug in: no electricity, no water, no drainage, no groundworks, so no building work in a regulated space.

Separation happens indoors, into a caddy, at the two places where the material appears: the vegetable prep area for peelings and trimmings, the wash-up for plate returns. The caddies are closed and washable, emptied at the end of service, and they go into the cleaning schedule like any gastronorm container. The route to the composter uses the existing waste exit, without creating an extra flow across the kitchen.

That leaves the legitimate dread of anyone responsible for HACCP: pests. The ABC composter is a 2 mm steel cylinder whose hatch stays shut between loads, and each load is covered with bulking agent: that is what separates it from a food waste bin left open. Odours, flies and rodents are covered in composting at work without odour or pests.

What the law requires of a catering operation

Separating food waste at source is a legal duty across the British Isles and Ireland, but the text that imposes it depends on where the kitchen is. In England, Simpler Recycling requires workplaces to have their food waste collected separately, the duty applying to employers of 10 or more full-time equivalent staff from 31 March 2025 and to the smallest from 31 March 2027. Scotland has required businesses to separate food waste since the Waste (Scotland) Regulations 2012, Wales since the Workplace Recycling rules of April 2024, and Northern Ireland under its own food waste regulations. In Ireland and the rest of the EU, Article 22 of Directive 2008/98/EC has required separate collection or recycling at source since 31 December 2023.

Public catering often carries a second, separate duty: reducing food waste at source, usually preceded by a measurement exercise. In England and Wales that expectation now sits alongside the recycling rules for larger organisations, and in Ireland and the EU it follows from the food waste reduction targets in the Waste Framework Directive. Weighing what goes into the composter already feeds that exercise.

Enforcement, and what you have to be able to show:

• in England the Environment Agency enforces the workplace recycling duty, and the waste transfer paperwork is the first thing an officer asks for;
• in Scotland, Wales and Northern Ireland the regulators are SEPA, Natural Resources Wales and the NIEA, each with its own powers and its own thresholds;
• in Ireland enforcement sits with the local authority, and the levels of penalty differ from one regime to the next: ask yours what applies to your site.

Any other scale of penalty circulating in a sales presentation is an invention. What actually triggers an inspection, and what you need to be able to produce that day, is a complete and dated series: the contract with your waste contractor, its transfer paperwork, and the weights recorded at each removal.

Two questions come up in every meeting. Does the composter need an environmental permit? Permitting thresholds are national, but the scale is very small: a composter that absorbs 1,500 kg a year treats about 4 kg a day, and in most regimes composting at the place where the waste is produced falls under a registered exemption rather than a full permit. Your environmental regulator confirms the position for your own site. What do you produce at an inspection? A weight and a transfer note at each removal, obtained from the contractor you appoint locally.

What comes with the composter

The 79 € excl. VAT a month of the ABC composter cover the equipment, the bulking agent resupplied, the maintenance and the replacement parts, the caddies with their stickers and the posters, and the team training by video call, which can be rerun as often as you need; the composter can also be bought outright. It arrives ready to use: a 2 mm steel body of 450 L, designed and built in our Picardy workshop. Two things to know before building a budget. Putting it in place is yours to do: two people, or a sack truck, are enough to move it to the spot you have chosen. And the removal of the mature compost is arranged with a local operator of your choice, which we help you scope. It is mixed by hand, on the crank, a few minutes a week: no electricity consumption and no separate maintenance contract to provision for.

Taking the finished material away is a separate decision. A site with grounds, a teaching garden or planters can keep its own compost and needs nothing else: that is the composter on its own. A site with nowhere to put it appoints a local waste contractor, and arranging collection sets out what to ask for. The comparison worth making is between a composter emptied a handful of times a year and a food waste bin on a weekly round: the number of vehicle movements is not of the same order.

Procurement and tenders

A school kitchen, a government canteen or a university refectory buys through public procurement, and the first question is always the procedure. Outside France the composter is available to buy outright or to lease over 48 months, and it needs no connection, so there is no works package attached to it. The thresholds that matter, the level below which you can buy directly, and the level at which a notice has to be published, are set by your own national rules, and the length of the commitment is what decides which side of them you fall. One point holds everywhere: the threshold is read per homogeneous requirement, so equipping fifteen sites at once is a single requirement and not fifteen small ones.

For a formalised tender, the selection paperwork depends on the buyer and differs from one country to the next. Beyond price, the criteria usually cover comparable references, traceability and local presence. On those points: the equipment is designed and built in our workshop in France ; the weight records come from the waste contractor you appoint locally, which keeps the traceability in your own contractual chain; and a real multi-site rollout is described in the Decathlon network case study. The countries we ship to are listed on our where we deliver page.

The checklist before you start

• Record the real number of covers served per day, not the theoretical capacity of the restaurant.
• Count the days of service over the year: around 220 in a staff restaurant, around 140 in a school.
• Multiply by 0.075 kg, then apply a 70% capture rate to get the volume that is genuinely compostable.
• Check that the result stays under 3,000 kg a year; if it does not, on-site composting is not the right answer.
• Identify around 1 m² of flat, load-bearing ground outside, on the existing waste route and reachable by a vehicle.
• Put one caddy in the vegetable prep area and one at the wash-up, and write them into the cleaning schedule.
• Name a lead in the kitchen and plan to reinstate the instruction every new term or with every new arrival.
• Keep the weight records and transfer notes from every removal: that is the evidence an inspector will ask for.
• Put the result alongside the food waste line of your current waste contract: that is the comparison that decides.

Common questions

How many covers a day can be composted on site?

Up to 129 covers a day with one composter and 259 with two, for a restaurant open 220 days a year. On a school calendar of 140 days, the thresholds rise to 204 and 408 covers a day. Above that, the volumes exceed 3,000 kg a year and on-site composting is no longer suitable.

Is a composter compatible with the HACCP rules of a catering kitchen?

The composter is not installed in the kitchen but outside, on around 1 m², away from food handling areas: the linear flow is preserved. Indoors, separation is done into a closed caddy in the vegetable prep area and at the wash-up, emptied at the end of service and written into the cleaning schedule.

Does composting a canteen's food waste need an environmental permit?

Permitting thresholds are set nationally, but the scale is very small: a composter that absorbs 1,500 kg a year treats about 4 kg a day. In most regimes, composting at the place where the waste is produced falls under a registered exemption rather than a full permit. Your environmental regulator confirms the position for your own site.

What does a canteen serving 100 covers need?

100 covers over 220 days come to 1,155 kg captured a year, which means one composter, its bulking agent and an arrangement for taking the finished material away. Renting the composter is 79 € excl. VAT a month, and buying one is possible after a conversation. In France, where collection is an option, 12 visits put the monthly figure at 199 € excl. VAT, bulking material, maintenance, awareness work and reporting included; elsewhere the removal of the mature compost is arranged with the local operator of your choice.

What if the canteen goes above 3,000 kg of food waste a year?

We do not offer on-site composting above 3,000 kg a year: two composters are a technical maximum, not a commercial choice. Those volumes then need a separate collection to an industrial composting site or an anaerobic digestion plant.

Where to start

In order: the number of covers, the number of days of service, then the sizing. All three steps are automated. The online sizing tool applies the ratio and the capture rate to the meals you serve and returns the number of composters, in your browser and with no sign-up.

With that figure in hand, go back to the food waste line of your waste contract: the comparison is a simple subtraction once you know how much of the stream leaves the site by composter rather than by lorry. The operational sequence, from delivery to the first emptying, is set out on the how it works page.