Compostable vs biodegradable packaging: what's the difference

Resparkle Natural Laundry Powder refill sachet, plastic-free industrially compostable packaging

By the Resparkle team, a small family business based in Brisbane. Last updated: 2026-05-26.

TL;DR

"Biodegradable" without further qualification is a near-meaningless marketing label. All organic materials biodegrade eventually; the word alone says nothing about how long it takes or under what conditions. "Compostable" is meaningless unless it references a defined standard. In Australia, the two standards that matter are AS 4736:2006 (industrial compostable: breaks down in a commercial composting facility at 55 to 60°C within 180 days) and AS 5810 (home compostable: breaks down in a domestic compost bin at ambient temperature within 180 days). When a brand says "plastic-free compostable packaging" and cites one of these standards, the claim is verifiable. When it says "biodegradable packaging" with nothing else, it is not.

Why "biodegradable" alone is not enough

Every material that was once organic will break down eventually. A plastic bottle made from petroleum-derived polymers will technically biodegrade, but the process takes hundreds of years and produces microplastics along the way. A paper bag will break down in weeks under the right conditions. A bioplastic bag made from cornstarch might break down in six months in a commercial composting facility, or never at all in a home compost bin.

"Biodegradable" without a timeframe and specified conditions is a non-statement. The ACCC's December 2023 guidance on environmental claims addresses this directly: claims that are technically true but omit important context (such as the conditions required for biodegradation to occur) can constitute misleading conduct under the Australian Consumer Law.

Three things a biodegradability claim must specify to be meaningful:

  1. What conditions are required? Temperature, humidity, microbial environment. Some bioplastics only degrade in industrial composting facilities running at 55 to 60°C. In ambient temperature (home compost, landfill, or nature), they behave like conventional plastic.
  2. What timeframe? Defined standards set maximum timeframes. A claim without a timeframe is unverifiable.
  3. What end products? Genuine composting produces CO2, water, and biomass. Fragmentation into microplastics (plastic bags breaking into smaller pieces in UV light) is not composting and is not biodegradation in the relevant sense.

The important part most buyers don't realise: some products labelled "biodegradable" break down only under industrial composting conditions that most household waste never sees. If they go to landfill or curbside recycling, they persist like conventional plastic.

The Australian standards that matter

Australia has two certified standards for compostable packaging, both set by Standards Australia and audited by the Australasian Bioplastics Association (ABA).

AS 4736:2006, Industrial compostable

This is the standard for packaging that breaks down in a commercial composting facility.

Key requirements under AS 4736:2006:

  • 90 percent biodegradation of the material's carbon content within 180 days at temperatures between 55 and 60°C.
  • Disintegration to less than 2mm fragments within 12 weeks under composting conditions.
  • No toxic effects on the resulting compost (measured by plant growth and worm tests).
  • Heavy metal content below defined thresholds.

What this means in practice: packaging certified to AS 4736 will break down in a commercial composting facility. It will not break down in a home compost bin (ambient temperatures are too low), and it may not break down in landfill (anaerobic, no microbial activity).

The certification mark: ABA's "seedling logo" (green leaf on a white background) indicates AS 4736 certification. A product displaying this mark has been independently audited.

AS 5810, Home compostable

This is the more demanding standard for packaging that breaks down in a domestic compost bin.

Key requirements under AS 5810:

  • 90 percent biodegradation within 180 days at ambient temperature conditions (around 20 to 30°C).
  • Disintegration consistent with compostable food waste within 180 days.
  • No toxic residues. No heavy metals above threshold.

What this means in practice: packaging certified to AS 5810 will break down in a home compost bin, alongside vegetable peelings and garden waste. It is a more stringent standard than AS 4736 because ambient temperature composting is slower and less aggressive than industrial composting.

The certification mark: ABA's "seedling with home" logo indicates AS 5810 home compostable certification.

Standard Full name Composting environment Temperature Timeframe
AS 4736:2006 Industrial Compostable Commercial composting facility 55 to 60°C 180 days
AS 5810 Home Compostable Domestic compost bin Ambient (20 to 30°C) 180 days

What the difference means for your bin

This table is the key practical takeaway.

Packaging claim What happens in home compost What happens in landfill What happens in commercial composting
AS 5810 certified home compostable Breaks down within 180 days May not break down (anaerobic conditions) Breaks down
AS 4736 certified industrial compostable Does NOT break down Does NOT break down Breaks down within 180 days
"Biodegradable" (no standard) Unknown Unknown Unknown
Conventional plastic Does not break down Does not break down Does not break down
"Recyclable plastic" Does not break down Does not break down Does not break down

Key takeaway: if your council does not have a commercial composting stream, industrially compostable packaging needs to go to a commercial composting facility to fulfil its end-of-life promise. That means it needs a disposal pathway beyond the household bin. Some brands offer take-back programmes (customers return used packaging for commercial composting). This is materially better than landfill, but it is not the same as home compostable, and a brand should be clear about which it is.

Why this distinction matters more than it used to

The ACCC's enforcement action against Clorox Australia (GLAD bags, "50% ocean plastic" claims, $8.25 million penalty in April 2025) put the cleaning products sector on notice: packaging claims, like any other environmental claim, must be precise and substantiated. The precision of "compostable to AS 4736" versus "biodegradable" is not a pedantic distinction. It is the difference between a claim that can be audited and one that cannot.

The ABA (Australasian Bioplastics Association) certifies manufacturers to both standards and maintains a public register of certified products. A packaging claim referencing ABA certification can be verified against that register.

For consumers evaluating laundry packaging:

  • "Plastic-free and certified compostable to AS 4736" is verifiable.
  • "Biodegradable bag" is not.
  • "Eco-friendly packaging" tells you nothing.

Common myths about compostable and biodegradable packaging

Myth: Compostable plastic breaks down in the ocean. Reality: Neither AS 4736 nor AS 5810 covers marine biodegradation. Compostable materials certified to these standards require microbial activity, humidity, and (for industrial) temperature. Open ocean conditions do not reliably provide these. The separate standard for marine biodegradation (being developed internationally) does not yet have an Australian certified equivalent. Any claim about ocean biodegradability should be viewed with significant scepticism.

Myth: "Plant-based plastic" is automatically compostable. Reality: PLA (polylactic acid), one of the most common plant-based plastics, is made from corn starch and is industrial compostable to AS 4736. But it is not home compostable and does not break down in landfill. "Plant-based" and "compostable" are independent properties. A plastic derived from plants is not automatically better for end-of-life outcomes.

Myth: Putting industrially compostable packaging in the recycling bin works. Reality: compostable packaging contaminates conventional plastic recycling streams. It looks like plastic, it processes like plastic in mechanical recycling, but it degrades in ways that compromise the output plastic. Compostable packaging belongs in a commercial composting stream (where available) or a take-back programme, not in yellow-lid recycling.

Myth: If it says "biodegradable" on the pack, it is safe to put in any bin. Reality: "Biodegradable" without a standard attached has no defined disposal pathway. Putting a "biodegradable" bag in landfill usually results in conventional landfill behaviour (slow, anaerobic, incomplete). The correct disposal pathway depends on which standard (if any) the product is certified to.

FAQ

What is the difference between compostable and biodegradable packaging? All compostable packaging is biodegradable, but not all biodegradable packaging is compostable. "Biodegradable" means a material will eventually break down, but without specifying timeframe or conditions. "Compostable" under Australian standards (AS 4736 for industrial, AS 5810 for home) requires breakdown within 180 days under defined conditions, with no toxic residue. Compostable is the more meaningful and verifiable claim.

What does AS 4736 mean on packaging? AS 4736:2006 is the Australian standard for industrial compostable packaging. It requires 90 percent biodegradation within 180 days at 55 to 60°C in a commercial composting facility, with no toxic residues. Packaging certified to AS 4736 by an ABA-audited body will carry the ABA seedling logo.

What does AS 5810 mean on packaging? AS 5810 is the Australian standard for home compostable packaging. It requires 90 percent biodegradation within 180 days at ambient temperature in a domestic compost bin, with no toxic residues. It is a more demanding standard than AS 4736 because ambient temperature composting is slower.

Can I put industrial compostable packaging in my home compost? No. Industrial compostable (AS 4736) packaging requires the elevated temperatures of a commercial composting facility (55 to 60°C). At ambient home compost temperatures, it will break down very slowly or not at all within a meaningful timeframe.

Is "plastic-free" packaging the same as compostable? Not necessarily. "Plastic-free" means no conventional petroleum-derived plastic. The packaging could be paper, cardboard, glass, or bioplastic. "Plastic-free" does not specify how it breaks down. A packaging product can be plastic-free and certified compostable, plastic-free and not compostable, or use bioplastic (plant-derived) that is plastic-free and industrial compostable but not home compostable.

Resparkle's packaging, explained

As a practical example: Resparkle Natural Laundry Powder ships in a bag described as "plastic-free industrially compostable." That means it meets the conditions for industrial composting (not home compostable). Resparkle also runs a bag take-back programme: customers accumulate 10 or more used bags and request a postage-paid return label for responsible disposal.

The take-back model exists because industrial compostable packaging needs a commercial composting pathway that most household bins do not provide. The honest framing is: it is materially better than conventional plastic packaging going to landfill, and the take-back programme creates a real disposal route rather than a theoretical one.

For broader plastic-free comparisons across laundry formats, see Best natural laundry detergent Australia 2026 and Best natural laundry powder Australia 2026. For how packaging claims relate to greenwashing more broadly, see Is your laundry detergent greenwashing?. For the eco powder format comparison that includes packaging as a ranked criterion, see Eco laundry powder Australia buyer's guide.

Sources

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