Condensed milk is cow's milk from which water has been removed. It is most often found in the form of sweetened condensed milk, with sugar added, and the two terms 'condensed milk' and 'sweetened condensed milk' are often used synonymously in the English language today. Sweetened condensed milk is a very thick, sweet product which when canned can last for years without refrigeration if unopened. Though there have been unsweetened condensed milk products, they spoiled far more easily and are uncommon today. Condensed milk is used in numerous dessert dishes in many countries, including the United States, Germany, Argentina, Brazil, Hong Kong SAR, Lebanon, Russia,  and Sri Lanka 

Condensed milk is used in recipes for the popular Brazilian candy brigadeiro, in which condensed milk is the main ingredient (the most famous condensed milk brand in Brazil is Moça , local version of Swiss Milch Mädchen marketed by Nestlé), lemon meringue pie, key lime pie, caramel candies, and other desserts.

In parts of Asia and Europe, sweetened condensed milk is the preferred milk to be added to coffee or tea. Many countries in Southeast Asia, such as Vietnam, use condensed milk to flavor their coffee; in Malaysia, teh tarik is made from tea mixed with condensed milk; and condensed milk is an integral element in Hong Kong tea culture. In the Canary Islands, it is served as the bottom stripe in a glass of the local café con leche. A popular treat in Asia is to put condensed milk on toast and eat it in a similar way as jam and toast. In West Yorkshire, in the years after World War II, condensed milk was an alternative to jam. Nestlé has even produced a squeeze bottle similar to Smucker's jam squeeze bottles for this very purpose. Condensed milk is a major ingredient in many Indian desserts and sweets. While most Indians start with normal milk to reduce and sweeten it, packaged condensed milk has also become popular.

In New Orleans, it is commonly used as a topping on top of a chocolate or similar cream flavor snowball. In Scotland, it is mixed with sugar and some butter and baked to form a popular, sweet candy called a Tablet or Swiss-Milk-tablet, this recipe being very similar to another version of the Brazilian candy brigadeiro called branquinho. In some parts of the Southern U.S., condensed milk is a key ingredient in lemon ice box pie, a sort of cream pie. In the Philippines, condensed milk is mixed with some evaporated milk and eggs, spooned into shallow metal containers over liquid caramelized sugar, and then steamed to make a stiffer and more filling version of crème caramel known as leche flan, also common in Brazil under the name pudim de leite.

In Mexico, sweetened condensed milk is one of the main ingredients of the cold cake dessert (The leading brand , the local version of Swiss Milch Mädchen by Nestlé), combined with evaporated milk, Marie biscuits, lemon juice, and tropical fruit. In Brazil, this recipe is also done exchanging fruit for puddings, most commonly vanilla and chocolate, known as torta de bolacha. It is also used to make homemade dulce de leche by baking it in an oven. In Brazil, it is common to do this by baking the closed can in a bain-marie, the result being doce de leite. In Britain and Ireland, the contents of a boiled can is used as the layer between biscuit base and the banana and cream level in banoffee.