Bees generally mate at a collective mating site while flying in midair. The female bees typically mate with several male bees to collect all the sperm needed to last their entire lifetime. Male honeybees and some other species of bees die after the mating process, while other species of bees mate with multiple females.

Depending on the species, female bees find shelter for the winter or return to their nest to lay their eggs. Solitary female bees build their nest and place food inside before laying the eggs. The construction of the nest, the food the bees use and the way the eggs are positioned are determined by the species of bee. Some species of bees lay one egg in each nest they build, while others divide the nest into multiple chambers. The majority of solitary bees seal the nest or the nest's chambers after laying the eggs. These bees typically lay their eggs in the fall, and the eggs hatch in the spring. This means that the bees never see their offspring because they die during the winter.

Social bees have a queen that lays thousands of eggs. The eggs are placed inside individual cells in the hive, and the queen controls whether the eggs she lays are male or female. The stored sperm of the queen bee produces females, while unfertilized eggs become males.