What is the Difference Between Compostable and Biodegradable? Unpacking the Eco-Friendly Labels

As sustainability becomes a household priority, terms like compostable and biodegradable are popping up more frequently on packaging, labels, and marketing materials. At first glance, they may seem interchangeable — both suggest environmentally friendly disposal methods. However, understanding the critical differences between compostable and biodegradable materials is essential for both individual consumers and businesses committed to true eco-conscious choices.

In this comprehensive article, we’ll explore what each term really means, the conditions required for decomposition, regulatory standards, and why the distinction matters when it comes to reducing environmental impact. Whether you’re trying to choose sustainable packaging, evaluate product labels, or advocate for greener practices, this guide will equip you with the knowledge you need.

Defining the Terms: Compostable vs. Biodegradable

Before diving into the distinctions, it’s important to clearly define these two commonly misunderstood terms.

What Does Biodegradable Mean?

A material is considered biodegradable if it can be broken down naturally by microorganisms such as bacteria, fungi, or algae into water, carbon dioxide, and biomass. This decomposition process occurs in a variety of environments, including soil, water, and even marine ecosystems.

However, there are few standardized requirements around timeframes or conditions for biodegradation. A material might be labeled biodegradable even if it takes decades to break down or leaves behind toxic residues. This lack of regulation has led to widespread greenwashing — misleading claims about a product’s environmental benefits.

What Does Compostable Mean?

In contrast, a compostable material is specifically designed to break down under controlled composting conditions. Composting involves a managed process of exposing organic material to heat, moisture, oxygen, and microorganisms, resulting in nutrient-rich compost that can be used to fertilize soil.

The critical distinction is that compostable materials:

• Must decompose within a specific timeframe, typically 90 to 180 days.
• Must leave no toxic residues or harmful byproducts.
• Must contribute to the formation of a beneficial end-product: compost.

Thus, while all compostable materials are technically biodegradable, not all biodegradable materials are compostable.

Conditions and Environments: Where and How Decomposition Occurs

The actual decomposition process depends heavily on the environment in which the material ends up.

Biodegradation: Variable Conditions

Biodegradable products break down under different conditions:

• Industrial composters: Controlled environments with high heat and optimal microbial activity.
• Home compost bins: Cooler, slower conditions; fewer materials can fully decompose here.
• Landfills: Anaerobic (oxygen-poor) environments where biodegradation is extremely slow and often produces methane — a potent greenhouse gas.
• Oceans or soil: Natural outdoor environments where timeframes vary widely.

Because of this variability, a product labeled “biodegradable” might only degrade efficiently in specific settings, and may not decompose at all in others.

Compostability Requires Specific Conditions

Compostable materials require a particular set of conditions to decompose properly:

This means that even certified compostable items may not decompose in a backyard compost pile or landfill. For example, compostable plastics like PLA (polylactic acid) require the high temperatures of industrial composting facilities to break down efficiently.

Standards and Certifications: How Are These Labels Verified?

Because environmental claims can be easily misused, independent certifications help verify a product’s compostability or biodegradability.

Compostable Certifications

Internationally recognized standards include:

• ASTM D6400 (USA): Specifies tests for plastic materials in composting facilities.
• EN 13432 (Europe): The European standard for packaging recoverable through composting and anaerobic digestion.
• AS 4736 (Australia): Similar to EN 13432, includes additional requirements for biodegradation in home compost systems.

Products certified under these standards must:
– Biodegrade at a high rate (typically ≥90% within 180 days).
– Disintegrate so that no visible fragments remain after screening.
– Be non-toxic to plants or soil.
– Leave behind compost that enriches soil.

Look for certification logos such as the “Seedling” logo (Europe) or the BPI (Biodegradable Products Institute) logo (USA) to verify authenticity.

Biodegradable Certifications

The landscape for biodegradable certifications is murkier:

• ASTM D5511: Measures anaerobic biodegradation.
• ASTM D5526: Evaluates biodegradation in landfill conditions.
• ISO 14855: Tests aerobic biodegradation under composting conditions.

However, the term “biodegradable” is often used without third-party verification, making it vulnerable to misuse. For example, petroleum-based plastic fragments labeled “biodegradable” may break into microplastics without truly returning to nature as harmless compounds.

Real-World Implications: What Happens When You Throw These Materials Away?

Understanding where materials go after disposal is crucial to assessing their environmental impact.

Compostable Items in Landfills

Even if a product is compostable, ending up in a landfill significantly undermines its benefits. Landfills are anaerobic environments — low in oxygen — which limits microbial activity and drastically slows decomposition. In fact, organic waste in landfills often produces methane, a greenhouse gas 25 times more potent than CO₂ over a 100-year period.

Worse, compostable plastics like PLA in landfills can persist for years and even contaminate recycling streams if not properly sorted.

Biodegradable Misconceptions

Many consumers assume “biodegradable” means “safe to litter.” That’s far from the truth. A biodegradable product tossed into the ocean may take years to break down and could still harm marine life. Additionally, some biodegradable additives simply cause plastics to fragment, turning them into microplastics without complete molecular breakdown.

For instance, oxo-degradable plastics — which break down when exposed to sunlight — are banned in the European Union due to their harmful impact on ecosystems.

Common Materials: Examples and Comparisons

Let’s examine some everyday materials to better illustrate the differences.

Compostable Examples

• Food scraps, yard waste, coffee grounds: Naturally compostable in home or industrial systems.
• Compostable bags (PLA-based): Made from cornstarch or other plant materials, certified for industrial composters.
• Certified compostable cutlery, plates, and cups: Often plant-based and designed to break down in commercial composting facilities.

These items contribute positively to soil health if composted correctly.

Biodegradable Examples

• Wood, cotton, paper: These biodegrade over time but may take longer depending on treatment (e.g., coated paper).
• Certain bioplastics (not certified): May degrade slowly or leave residues.
• “Biodegradable” synthetic fabrics: Some claim rapid breakdown but lack independent verification.

The key takeaway is that biodegradable doesn’t guarantee quick, safe, or complete decomposition.

Home Composting vs. Industrial Composting: Do You Need Both?

Understanding the difference between home and industrial composting is essential when choosing compostable products.

Home Composting

Most backyard composters operate at temperatures of 20–40°C. This is sufficient for food waste and paper, but too cool for many compostable plastics. Only materials certified for home composting, such as those bearing the AS 5810 (Australia) label or OK Compost HOME certification, will reliably break down in a home bin.

Industrial Composting

Industrial facilities maintain high heat and actively manage conditions to speed decomposition. They can process a broader range of compostable materials, including many bioplastics. However, access to such facilities varies by region — many urban areas still lack widespread infrastructure.

This creates a gap: certified compostable items may end up in landfills simply because consumers can’t access composting facilities.

Environmental Impact: Which Is Better for the Planet?

When comparing environmental outcomes, compostable products — when properly managed — often offer greater benefits.

Benefits of Compostable Materials

• Reduce organic waste in landfills and lower methane emissions.
• Create nutrient-rich compost that improves soil structure and water retention.
• Support a circular economy where waste is returned to nourish new growth.

For example, composting food waste alone could reduce greenhouse gas emissions equivalent to taking 7.8 million cars off the road annually in the U.S.

Concerns with Biodegradable Products

• Timeframes are undefined, meaning biodegradation does not equate to urgency.
• Potential for toxic residue if breakdown is incomplete.
• Risk of contamination in recycling or composting streams.

Additionally, some “biodegradable” claims are purely marketing tactics. Studies have shown that items labeled biodegradable are more likely to be littered, as people believe nature will “take care of it.”

Challenges in Waste Management and Consumer Awareness

Even with better materials, systemic challenges remain.

Lack of Infrastructure

In the United States, only about 9% of compostable waste is actually composted, according to the U.S. Composting Council. Most curbside waste systems don’t include compost collection, and consumers often don’t know how to handle compostable packaging.

Consumer Confusion

A 2021 study by the European Commission found that over 60% of consumers believe biodegradable means the product will break down quickly in any environment. This misunderstanding leads to misuse and undermines waste sorting efforts.

Clear labeling, education campaigns, and standardized packaging language are essential to closing this awareness gap.

Contamination of Recycling Streams

Compostable plastics in recycling bins can contaminate recyclable plastics. Because they look and feel similar to conventional plastics, they’re difficult to sort and can compromise the quality of recycled material. This is especially true in mixed recycling systems without advanced sorting technology.

The Role of Businesses and Policymakers

Achieving a sustainable future requires more than consumer awareness — it involves shifts at the industry and policy level.

Corporate Responsibility

Brands must:
– Avoid misleading terms like “eco-friendly” without substantiation.
– Clearly label products as “compostable in industrial facilities only.”
– Invest in materials that meet recognized certifications.
– Design packaging with end-of-life in mind.

Leading companies like Patagonia and Seventh Generation have integrated transparent lifecycle assessments into their product development, minimizing greenwashing.

Policy and Infrastructure Investment

Governments play a vital role by:
– Banning oxo-degradable plastics and regulating the use of the term “biodegradable.”
– Expanding composting infrastructure through public-private partnerships.
– Implementing mandatory organics recycling programs, like those in California and Seattle.
– Providing education funding on proper waste disposal methods.

The European Union’s Single-Use Plastics Directive is a model example, combining bans on harmful materials with support for alternatives that are genuinely compostable under specific conditions.

How to Make Smarter Choices: A Consumer’s Guide

You don’t need to be a scientist to make informed decisions. Follow these tips to avoid the pitfalls of vague environmental claims.

Read the Labels — and the Fine Print

Look for certifications like:
– BPI (USA)
– OK Compost INDUSTRIAL or HOME (Europe)
– AS 4736 or AS 5810 (Australia)

If a product only says “biodegradable” with no certification, approach with skepticism.

Know Your Local Waste System

Call your local waste management provider to find out:
– Do they collect food and yard waste for composting?
– Do they accept compostable packaging?
– Are there drop-off locations for industrial composting?

If composting isn’t available, choosing compostable packaging may not be the best option — reusable alternatives might be better.

When in Doubt, Opt for Reusable or Recyclable

Compostable and biodegradable options aren’t always superior. A reusable metal straw or cotton bag provides more environmental benefit than multiple disposable “biodegradable” versions, especially if the latter end up in landfills.

Advocate for Change

Support businesses using certified compostable materials. Demand clearer labeling laws from regulators. Participate in community composting programs, or start one if one doesn’t exist.

Looking Ahead: The Future of Sustainable Materials

The future of packaging and disposables is evolving rapidly.

Innovations in Material Science

Researchers are developing materials that:
– Break down efficiently in marine environments.
– Function in both industrial and home compost systems.
– Are made from agricultural waste (e.g., banana peels, sugarcane bagasse).

For example, companies like Notpla and Ecovative are creating seaweed-based and mycelium-based packaging that dissolves in water or composts safely.

Smarter Labeling and Tracking

Emerging technologies like QR codes on packaging could provide consumers with real-time information about disposal methods, regional composting access, and environmental impact data.

Waste-to-Resource Models

As the circular economy gains traction, organic waste — including compostable materials — is being seen not as garbage but as a resource stream. Cities may eventually mandate separation of organics, turning food scraps and compostable packaging into energy or fertilizer.

Conclusion: Choosing Clarity Over Confusion

The difference between compostable and biodegradable is more than just semantics — it’s a matter of environmental accountability. While both terms describe materials that can break down, compostable has stricter scientific and regulatory criteria, making it the more reliable and eco-responsible label.

True sustainability requires more than choosing “green” packaging. It demands understanding how materials behave in the real world, supporting policy change, and building infrastructure that closes the loop.

As consumers, the best thing we can do is demand clarity, transparency, and integrity from companies. Look for certifications. Know where your waste goes. And never assume that “biodegradable” means “harmless.”

By prioritizing compostable — especially certified, regionally supported composting systems — we can move closer to a world where waste nourishes the earth, rather than pollutes it.

What does the term biodegradable mean?

The term biodegradable refers to the ability of a material to break down naturally through the action of microorganisms such as bacteria, fungi, and algae. Biodegradation results in the material being converted into natural elements like water, carbon dioxide, and biomass over time. However, the timeline for this process can vary significantly—some biodegradable materials may degrade within weeks, while others can take years, depending on environmental conditions like temperature, moisture, and oxygen levels.

It’s important to note that “biodegradable” is a broad term and lacks strict regulatory standards in many regions, meaning virtually any organic material could technically be labeled as such, even if it degrades slowly or leaves behind harmful residues. For example, conventional plastics may be marketed as biodegradable, but they often break down into microplastics rather than fully integrating into ecosystems. As such, the term alone doesn’t guarantee environmental safety or a swift, complete decomposition process.

What does compostable mean in environmental terms?

Compostable materials are substances that can break down into non-toxic, natural components under specific composting conditions, which typically include controlled levels of heat, moisture, oxygen, and microbial activity. Unlike general biodegradability, compostable products are designed to decompose within a defined timeframe—usually within 90 days in industrial composting facilities—and contribute to the creation of nutrient-rich compost that benefits soil health. This compost can then be used to support plant growth and enrich agricultural fields.

To be labeled compostable, a product must meet rigorous standards, such as those set by the ASTM or the European Norm EN 13432. These standards ensure that the item not only breaks down efficiently but also does not leave behind toxic residues or harmful microplastics. Home compostable items are a subset that break down in less controlled backyard compost piles, though many compostable plastics require high temperatures only found in industrial facilities. This makes proper disposal critical to realizing their environmental benefits.

Are all biodegradable products compostable?

No, not all biodegradable products are compostable. While both involve natural breakdown, compostability is a more specific and stricter category than biodegradability. A compostable product must degrade completely into organic matter within a set period under composting conditions and provide value as a soil enhancer. In contrast, a biodegradable item may decompose slowly, break down into fragments, or leave behind residues that aren’t beneficial or safe for the soil.

For example, a wood-based coffee stirrer may be both biodegradable and compostable, whereas a so-called “biodegradable” plastic bag might fragment over time but not fully break down into compost. Additionally, some biodegradable products require unique environmental conditions to degrade—conditions not found in home compost bins or landfills—rendering them ineffective in typical waste processing systems. Therefore, assuming biodegradable items can be added to compost heaps may lead to contamination.

Can compostable products break down in a landfill?

Compostable products are not designed to break down efficiently in landfills. Landfills are typically anaerobic environments, meaning they lack oxygen, which is essential for the decomposition process required by compostable materials. Without sufficient oxygen, heat, and microbial activity found in composting facilities, compostable items may break down very slowly or remain intact for years, similar to conventional plastics.

Moreover, when compostable materials decompose in landfills without proper conditions, they can release methane—a potent greenhouse gas—contributing to climate change. This defeat the purpose of using compostable products to reduce environmental impact. To maximize their benefit, compostable items should be disposed of in industrial or home composting systems, not thrown in the trash. Consumers need access to proper waste separation and composting infrastructure to ensure these materials fulfill their eco-friendly potential.

What are the environmental benefits of compostable products?

Compostable products offer several environmental benefits when properly managed. They are typically made from renewable resources like corn starch, sugarcane, or other plant-based materials, reducing dependence on fossil fuels used in traditional plastic manufacturing. When composted correctly, these materials transform into nutrient-rich humus that enhances soil structure, increases water retention, and supports healthy plant growth, thereby promoting sustainable agriculture and reducing the need for chemical fertilizers.

Additionally, compostable products help divert organic waste from landfills, reducing methane emissions and overall waste volume. By integrating into a circular economy—where waste becomes a resource—they contribute to closing the loop on materials use. However, these benefits are only realized when composting infrastructure is available and consumers correctly dispose of the items. Without proper systems, compostable products may cause contamination or fail to break down, limiting their positive impact.

How can consumers identify truly compostable products?

Consumers can identify truly compostable products by looking for third-party certification labels from recognized organizations. Labels such as the “Compostable” logo from the Biodegradable Products Institute (BPI), the Seedling logo (European certification), or the Australian Standard AS 4736 indicate that the product has passed tests for disintegration, biodegradation, and lack of ecotoxicity under industrial composting conditions. These certifications ensure the material meets specific scientific and environmental standards.

In addition to checking for certifications, consumers should read packaging carefully to determine whether a product is suitable for industrial composting or can be composted at home. Some compostable items, like certain PLA plastics, require high temperatures only achievable in commercial facilities. Educating oneself about local waste management options—such as municipal composting programs—can also help ensure that compostable products are disposed of correctly and actually end up being composted rather than contaminating recycling streams or landfills.

Why is it important to distinguish between compostable and biodegradable?

Distinguishing between compostable and biodegradable is essential to avoid greenwashing and ensure environmentally responsible choices. Misunderstanding these terms can lead consumers to believe they are making sustainable decisions when, in reality, the products may not break down as expected or could harm ecosystems. For example, placing a “biodegradable” plastic in a backyard compost bin may leave behind persistent fragments, while dropping a certified compostable cup into the trash negates its benefits.

Clear differences also guide proper waste sorting and disposal behavior. Knowing that compostable materials require specific processing conditions helps consumers support effective waste management systems. Furthermore, businesses and policymakers rely on these distinctions to develop standards, labeling requirements, and infrastructure that promote genuine sustainability. Accurate understanding empowers individuals and institutions to reduce pollution, conserve resources, and contribute to a healthier planet.