Compostable bags are made of natural plant starch, and do not produce any toxic material. Compostable bags break down readily in a composting system through microbial activity to form compost. In order to be classified as compostable they must meet the Australian Standard for composability AS4736 and will have this symbol.

Compostable bags are an eco-friendly alternative to traditional plastic bags. Unlike plastic, these are made from natural materials like coffee grounds, cornstarch, or vegetable oil. As a result, they break down into compost, which can be used to fertilize the soil. These are also typically stronger than plastic ones, so they can better resist tearing and breaking.

Compostable bags are important because they help to reduce the amount of waste that ends up in landfills. Unlike traditional plastics, these can be broken down by bacteria and other microorganisms. This process, known as composting, results in the production of beneficial compost that can be used to improve soil quality.

In addition to reducing the amount of waste in landfills, these also help to reduce greenhouse gas emissions. The process of decomposing organic matter in the anaerobic conditions of a landfill releases methane, a powerful greenhouse gas. However, when compost is properly managed, it can serve as a carbon sink, helping offset some of the methane emissions from other sources. As a result, compostable bags play an important role in mitigating climate change.