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Commercial composting explained: Methods, processes and benefits

Commercial composting is the process of turning food and organic waste from businesses into nutrient-rich compost instead of sending it to landfill.

Food waste in landfills releases methane, a potent greenhouse gas that drives climate change. Commercial food waste obligations are becoming stricter in the UK, meaning that businesses are required to find alternative methods, such as composting, to dispose of their organic waste responsibly.

This guide explains how commercial composting works, the methods available, and why it’s worth considering for your business.

What is commercial composting?

Commercial composting is the large-scale processing of organic waste such as food scraps, garden waste, and other biodegradable materials into nutrient-rich compost. This compost is then used to enhance soil quality in agricultural, landscaping, and land restoration projects.

The process works by accelerating natural decomposition under controlled conditions. Microorganisms break down the waste in the presence of oxygen, producing far fewer greenhouse gases than if the same material were left to rot in a landfill, where it would release methane.

While small businesses may manage some food waste on-site using compost bins or digesters, most rely on off-site commercial composting services. These are better suited to handling larger waste volumes and meeting local compliance requirements.

Commercial composting is an effective way for businesses to reduce landfill waste, cut disposal costs, and contribute to environmental goals.

What waste can be composted?

Many types of everyday business waste can be composted, provided the right methods and facilities are used. In commercial settings, composting works best when waste is separated correctly at the source.

Compostable business waste includes:

Food scraps such as vegetable peelings, fruit cores, and plate leftovers
Coffee grounds and tea bags (check for plastic content)
Compostable paper and cardboard, like napkins, pizza boxes, and shredded documents
Garden clippings, hedge trimmings, and leaves from grounds maintenance

Waste that needs care or special methods:

Some waste types require specific conditions to be composted safely:

Meat, dairy, and cooked food waste can attract pests and produce odours in basic composting systems. These materials are best handled through in-vessel composting.
Biodegradable plastics (e.g. compostable packaging or liners) typically need high-temperature conditions only found in industrial composting facilities. These do not break down in standard compost bins.
Pet waste and diseased plants are often excluded from both domestic and commercial composting due to potential health risks.

For businesses, it’s essential to check with your composting provider or waste contractor to understand what can and can’t be accepted.

Commercial composting methods

There are several types of commercial composting methods used across the UK, ranging from large-scale industrial systems to small-scale setups suitable for businesses managing waste on-site.

Each method is suited to different types of organic waste and may require permits or certifications, particularly for food waste handling.

Open windrow composting

Open windrow composting involves placing garden and green waste in long rows (called windrows) that are regularly turned to introduce oxygen and speed up the composting process.

Best for: garden waste, wood trimmings, hedge cuttings
Not suitable for: food waste or animal by-products (due to hygiene and pest concerns)
Permits: Operators must comply with PAS 100 quality standards and have the appropriate Environment Agency permit

This is one of the most widely used systems for commercial garden waste disposal.

In-vessel composting (IVC)

In-vessel composting is a closed system that enables tighter control over temperature, moisture, and airflow. This method is suitable for composting food waste, meat, dairy, and cooked materials.

Best for: mixed organic waste, including cooked and uncooked food
Process: waste is shredded and enclosed in a sealed vessel, where it is actively aerated and monitored
Permits: Sites must meet PAS 100 standards and hold relevant permits for handling animal by-products

Because the system prevents contamination and controls odours, IVC is the preferred method for composting in urban areas or near sensitive sites.

Anaerobic digestion (AD)

Anaerobic digestion breaks down organic waste in the absence of oxygen, producing biogas (used as renewable energy) and a nutrient-rich digestate.

Best for: food waste, liquids, and slurries
By-products: renewable energy (methane) and digestate fertiliser
Note: AD is not composting, but is often used alongside or as an alternative in food waste processing

Anaerobic digestion supports circular economy goals by turning waste into usable energy while reducing landfill volumes.

Small-scale commercial composting

Small-scale commercial composting refers to on-site systems that enable businesses to manage their organic waste without relying on external waste collection services.

These include:

Rotating compost tumblers
Hot composting bins
Bokashi systems for fermented food waste pre-treatment

Small cafes, schools, community centres, or rural businesses with space typically use these.. However, food waste composted on-site must still comply with animal by-product regulations, and some setups may require registration with the local authority or Environment Agency.

Industrial composting plants

Large industrial composting plants process organic waste collected from multiple businesses and local authorities.

These facilities typically use a combination of in-vessel and open windrow composting, depending on the waste streams. They are highly regulated and operate under PAS 100 certification and Environmental Permitting Regulations.

For businesses without the capacity or need to compost on-site, partnering with a waste carrier that sends food waste to one of these plants is often the most practical solution.

How the commercial composting process works

Commercial composting follows a structured, multi-stage process that safely and efficiently transforms organic waste into nutrient-rich compost. Each step must be carefully managed to ensure compliance with environmental regulations and produce a consistent, high-quality end product.

Here’s a breakdown of how it works:

1. Collection and segregation

The composting journey starts at the source. Businesses must segregate compostable waste from general waste, commercial glass recycling, commercial cardboard recycling and other recyclable materials.

Collection bins are provided for food waste, garden clippings, cardboard, and other compostable materials.
Contamination control is critical. Items like plastics, glass, metal, and certain food packaging must be kept out to avoid disrupting the composting process.
In some cases, separate bins are provided for meat, dairy, or cooked food if they’re being handled through in-vessel composting or anaerobic digestion.

Waste is collected by licensed waste carriers and transported to a composting facility. All handlers must comply with Duty of Care regulations and have appropriate waste carrier licences.

2. Waste preparation

Once the organic waste arrives at the facility, it is prepared for composting:

Sorting and inspection: Loads are inspected for contamination, and any non-compostable materials are removed.
Shredding: Waste is shredded to a uniform size, which accelerates decomposition and ensures even airflow during composting.
Blending: A balanced carbon-to-nitrogen ratio is key. Green waste (rich in nitrogen) is often mixed with dry materials like shredded cardboard or wood chips (high in carbon) to optimise the composting process.

This preparation stage helps create the ideal conditions for microbial activity and efficient breakdown of materials.

3. Active composting

This is the core stage where microorganisms break down the waste into compost:

Oxygen is introduced through turning (in open windrow systems) or forced aeration (in closed vessels).
Heat is generated naturally as microbes digest the material, with temperatures reaching 55–65°C, hot enough to kill off harmful pathogens.
Compost is regularly monitored for temperature, moisture, and oxygen levels to keep the process stable and compliant.

The active composting phase typically lasts 2 to 4 weeks in in-vessel systems, and up to 12 weeks in open windrow setups.

4. Maturation

Once active composting is complete, the material needs time to mature and stabilise:

Compost is moved to a curing area, where it continues to break down at a slower pace.
This phase typically lasts 1 to 3 months, depending on the method and the desired quality of the end product.
During this time, microbial activity decreases, and the compost develops the earthy smell and crumbly texture associated with high-quality soil amendment.

Skipping or shortening the maturation stage can result in immature compost that may harm plants or release excess nutrients too quickly.

5. Screening and harvesting

The final compost is then screened, tested, and packaged for use:

Screening removes any large particles or contaminants that didn’t break down, ensuring a uniform texture.
Compost is then tested for stability, contaminants, and nutrient content to meet PAS 100 standards where applicable.
Once approved, it is bagged or bulk-loaded for sale and use in agriculture, landscaping, horticulture, or land remediation projects.

High-quality compost is a valuable product that helps close the loop between waste generation and land restoration, turning business waste into a soil-enhancing asset.

Regulations and qualifications for composting

Commercial composting in the UK is highly regulated to ensure environmental protection, hygiene standards, and the quality of the final compost product.

Open windrow composting regulations

Operators of open windrow composting systems must hold an environmental permit from the Environment Agency and adhere to standard rules regarding feedstock types, site size, and odour control.

This method is typically only permitted for green waste, as it’s not suitable for processing food or animal by-products due to hygiene risks.

In-vessel composting regulations

In-vessel composting) Facilities, which are designed to handle food waste, including meat and dairy, are subject to tighter controls. They must also be fully permitted and comply with the Animal By‑Products Regulations (ABPR).

These rules establish strict temperature and processing time requirements to ensure that pathogens are destroyed, especially when catering to waste or meat is involved.

Sites must separate clean and dirty zones to prevent cross-contamination and protect public and animal health.

General commercial composting regulations

Regardless of the method used, to achieve End-of-Waste status and legally sell compost for agricultural or landscaping purposes, producers must be certified under PAS 100 and registered with the Compost Certification Scheme (CCS). This involves routine sampling, testing for contaminants, and demonstrating consistent quality.

Small business composting regulations

For small businesses and community groups, T23 exemptions allow aerobic composting without a full environmental permit. These exemptions apply to sites handling up to 80 tonnes of suitable waste (such as green waste and cardboard) per year, provided the compost is used on the same site or within a nearby location.

How businesses can start composting

Getting started with composting involves more than just separating food waste. To make it work effectively, you’ll need the right setup, staff training, and ongoing monitoring. Here’s a step-by-step approach to help your organisation launch a successful composting programme.

Step 1 – Waste audit

Start by reviewing the volume and types of organic waste your organisation produces each week. Common materials include:

Food preparation scraps and leftovers
Coffee grounds, paper towels, and compostable packaging
Garden or grounds maintenance waste

A simple waste audit helps determine whether on-site composting is realistic or if outsourcing is a more sensible option. It also highlights opportunities to reduce waste overall.

Step 2 – Choose method (on-site vs outsourced)

Once you understand your waste profile, choose the most suitable composting method:

On-site composting is an option if you have outdoor space or lower waste volumes. Solutions include:
- - Compost bins or hot composters for mixed organic waste
  - Wormeries (vermicomposting) for indoor or small-space use
  - Compact in-vessel systems for controlled, compliant composting
Outsourced composting is better suited to higher waste volumes or limited space. This involves partnering with a licensed composting provider who will collect and process your waste at an external facility.

Always check whether local regulations apply, especially for food waste containing meat, dairy, or packaging.

Step 3 – Training and monitoring

Engaging your team is essential for a successful composting setup.

Train staff on what can and can’t be composted
Use clearly labelled commercial waste bins and signage
Monitor waste areas regularly for contamination
Assign someone to oversee the process and report issues

Even small amounts of non-compostable waste, like plastic or glass, can compromise the entire batch.

Step 4 – Assess and improve

After the first 6 to 12 months, evaluate your composting efforts:

How much organic waste is being diverted from general disposal?
Have commercial waste costs reduced?
Are staff consistently following procedures?
Is your process compliant and easy to manage?

Use what you learn to fine-tune your approach, whether that’s adding new bins, refreshing training, or switching providers as your needs change.

Benefits of commercial composting

Composting isn’t just about waste reduction; it offers real value across financial, environmental, and social areas. Here are the key benefits for businesses using commercial composting:

Financial savings

Diverting food and organic waste from landfills can result in significant cost savings.

Compostable waste is typically lighter than general waste, resulting in lower collection fees, and it avoids landfill tax, which continues to rise year after year. Businesses that separate waste effectively may also reduce the number of general waste collections required.

Over time, composting can form part of a broader waste reduction strategy that lowers overheads and improves operational efficiency.

Environmental gains

Composting plays a direct role in reducing the environmental impact of commercial waste. Keeping food waste out of landfills helps cut methane emissions, a powerful greenhouse gas. It also reduces the demand for landfill space, helping to preserve land and minimise transport-related emissions from waste logistics.

Switching to composting is a practical and measurable way to support environmental responsibility.

Circular economy and soil health

Composted material serves as a valuable soil amendment that can be utilised in agriculture, landscaping, and land regeneration. This supports the circular economy by converting waste into a useful resource, reducing reliance on chemical fertilisers and improving long-term soil health.

It also closes the loop between consumption and regeneration, a key goal in sustainable waste practices.

Compliance and ESG reporting

As environmental legislation becomes stricter, composting enables businesses to stay compliant with commercial waste regulations and contribute to the country’s national Net Zero targets. It also supports ESG (Environmental, Social and Governance) reporting by providing tangible evidence of action on waste and emissions.

Composting can be included in sustainability reports, investor updates, and supply chain audits, particularly in food, hospitality, and retail sectors.

Employee and community benefits

On-site composting and clear recycling systems help engage staff, increase awareness, and support wider Corporate Social Responsibility efforts. Some businesses also use compost to support community gardens, green spaces, or employee wellbeing initiatives, creating visible and localised benefits from their waste reduction efforts.

This makes composting not only an operational decision but a cultural one that can improve team morale and external reputation.

Examples of outsourcing commercial composting

Many businesses outsource their composting through licensed waste carriers, who collect food or garden waste and deliver it to local composting or biofuel facilities.

These commercial sites process millions of tonnes of organic material annually, supporting both landfill diversion and circular economy goals.

The UK currently has around 272 permitted composting facilities, handling over 6.8 million tonnes of organic waste from homes and businesses each year. The resulting compost is used in agriculture and landscaping, with approximately two-thirds sold off-site for reuse.

Here are three examples of how commercial composting works in practice:

Veolia’s Southwark facility – open windrow composting

At Veolia’s Green Energy plant in Southwark, collected green waste is processed using open windrow composting.

This facility processes approximately 20,000 tonnes of garden waste each year. The compost produced meets the PAS 100 standard, making it suitable for widespread use in horticulture and land restoration.

This London commercial waste facility plays a key role in diverting organic waste from landfill and supports reliable collections for businesses across the capital.

New Earth Solutions (Kent) – in-vessel composting (IVC)

In Kent, New Earth Solutions operates a commercial composting site that uses in-vessel composting (IVC) to process a mix of food and garden waste.

The facility handles approximately 60,000 tonnes of organic waste annually, producing high-quality, PAS 100-certified compost. It also supports commercial waste collection in Kent, offering a compliant and scalable solution for businesses needing reliable food waste treatment.

Recyclus Group (Wolverhampton) – organics and lithium-ion recovery

Recyclus Group’s site in Wolverhampton is the UK’s first industrial-scale facility dedicated to black mass recycling, processing end-of-life lithium-ion batteries to recover valuable materials used in battery manufacturing.

While its core focus is on battery recovery, the site also supports emerging initiatives in organics and compostable packaging processing, reflecting a growing crossover between food waste treatment and high-tech recycling infrastructure.

Current issues with commercial composting

While commercial composting offers clear environmental and financial benefits, businesses and waste providers still face challenges that must be navigated. Understanding these limitations can help you plan a more practical and compliant approach to food and garden waste disposal.

Costs of equipment and permits

Setting up on-site composting systems, especially for food waste, can be costly. Equipment such as in-vessel composters or wormeries requires upfront investment, and in some cases, regular maintenance or energy input.

Larger setups may also require an environmental permit, which adds to the project’s cost and complexity.

This makes outsourced composting a more viable option for many businesses, despite the recurring collection fees.

Space restrictions

Not all sites have the space needed for compost bins or containers. Outdoor areas may be limited or unsuitable due to odour control issues, local restrictions, or inadequate drainage.

For urban businesses, especially those in multi-tenanted buildings, even small-scale composting can be difficult without landlord support or shared waste infrastructure.

Contamination risk

Successful composting depends on effective waste segregation. Contamination from plastics, glass, or metals can ruin entire batches of compost, result in regulatory non-compliance, and increase disposal costs.

Staff training and clear signage are essential, but enforcement can be challenging, especially in fast-paced environments such as hospitality or manufacturing.

Logistics of food waste collection

Even when using an external provider, the logistics of regular commercial food waste collection can be a challenge. Businesses may struggle with collection frequency, bin hygiene, and storage between pickups.

Not all waste providers offer food waste collection routes in every area, which can make composting unavailable or prohibitively expensive for some.