Billingsgate Fish Market is located in Poplar in London. It is the United Kingdom's largest inland fish market. It takes its name from Billingsgate, a ward in the south-east corner of the City of London, where the riverside market was originally established. In its original location in the 19th century, Billingsgate was the largest fish market in the world.

A fish market is a marketplace for selling fish and fish products. It can be dedicated to wholesale trade between fishermen and fish merchants, or to the sale of seafood to individual consumers, or to both. Retail fish markets, a type of wet market, often sell street food as well.