Retailers The Co-operative has made compostable carrier bags available to consumers at around 400 food stores, in what it says is a first for the UK.
The bags are certified to the EN13432 standard and carry the EU-wide seedling logo, which both indicate the compostability of plastic products.
Co-operative food environment manager Iain Ferguson said the move made the Co-operative the only major food retailer in the UK to offer such bags.
The roll-out follows the success of a trial in parts of the UK. The initiative has now been extended to 81 local authority areas with food recycling schemes that require householders to use compostable bags for food waste.
Compostable bags could reduce help in reducing the number of plastics bag ending up in landfill and could encourage more people to recycle food waste, said Ferguson.
The bags are sold at 6p each.
The initiative was launched amid a row on an upcoming five pence plastics bags levy, from which biodegradable bags are set to be excluded.