The northern fulmar, fulmar, or Arctic fulmar is a highly abundant seabird found primarily in subarctic regions of the North Atlantic and North Pacific oceans. There has been one confirmed sighting in the Southern Hemisphere, with a single bird seen south of New Zealand. Fulmars come in one of two color morphs: a light one, with white head and body and gray wings and tail, and a dark one, which is uniformly gray. Though similar in appearance to gulls, fulmars are in fact members of the family Procellariidae, which include petrels and shearwaters.

The fulmars are tubenosed seabirds of the family Procellariidae. The family includes two extant species and two extinct fossil species from the Miocene.