Fish chowder is a type of thick fish stew that is eaten in many parts of the world. Like other types of stew, fish chowder was traditionally eaten by the poorer people in an area and contained whatever ingredients were on hand. In modern times, fish chowder is enjoyed by all classes, and a number of recipes have been invented. There are now a number of fish chowders with recognizable flavors and ingredients, such as New England fish chowder.

The most important ingredient in fish chowder is fish. Any type of fish can be used in a chowder. Traditionally, this would have been whatever fish was on hand. Depending on the recipe being used, a mild-flavored white ocean fish or a more distinctively-flavored fish, such as salmon, may be preferred. Throughout Europe and North America, in many coastal towns and cities, the local fish is used in fish chowder. Most of the time, it is cut into bite-sized cubes before it is put in the chowder.

It is also common, though not necessary, to put vegetables into fish chowder. Potatoes are often added because they add a starchy component to the stew, making it more filling, and onions are often included for the flavor that they give to the stew. Any vegetables on hand can be used as long as the flavor of the vegetables complements the fish. Corn, carrots, squash, and tomatoes are all acceptable to include.

The liquid in fish chowder also varies from recipe to recipe. New England chowder, which can be made with fish or clams, is a well-known variety of chowder that uses milk and cream as the base. It is also possible to use a tomato broth instead of a cream broth or to combine cream and tomatoes. Fish stock, vegetable stock, or plain water can also be used. Most chowder recipes will also call for herbs and spices to be added to the broth. Chowders can be thickened with flour or by allowing them to reduce so that the liquid evaporates while the flavors remain.

Fish chowder is traditionally cooked in a pot called a caldaria or a cauldron. The ingredients are placed inside and allowed to boil until everything is cooked through. Modern cooks generally use soup pots to cook chowder, though the same cooking process is still used.