This is a mysticete family of two genera and three species. They are found near in most waters of the temperate and polar regions. Right and bowhead whales are large whales, reaching up to 18 m in length and over 100,000 kg weight. The dorsal fin is either lacking.
Flippers are short and rounded.
The throats of balaenids are smooth, lacking the furrows or grooves of some other mysticetes. The skull of balaenids has reduced nasals, and the frontals are barely exposed on the dorsal surface. The posterior border of the nasals and premaxillae lie anterior to the supraorbital processes of the frontals. The rostrum is high, narrow, and arched. Baleen plates are long and narrow, and they number more than 350 on each side of the upper jaw.