Plastic shopping bags, carrier bags, or plastic grocery bags are a type of plastic bag used as shopping bags and made from various kinds of plastic. In use by consumers worldwide since the 1960s, these bags are sometimes called single-use bags, referring to carrying items from a store to a home. However, it is rare for bags to be worn out after single use and in the past some retailers (like Tesco and Sainsbury's in the UK) incentivised customers to reuse 'single use' bags by offering loyalty points to those doing so. Even after they are no longer used for shopping reuse for storage or trash is common, and modern plastic shopping bags are increasingly recyclable or compostable. In recent decades, numerous countries have introduced legislation restricting the sale of plastic bags, in a bid to reduce littering and plastic pollution.

Some reusable shopping bags are made of plastic film, fibers, or fabric.