Hylaeus relegatus, also known as the Māori masked bee, is a bee species in the family Colletidae. It is endemic to New Zealand and was first described by Frederick Smith. It is the largest and most common species of this genus in that country. H. relegatus can be found throughout the three main islands of New Zealand and visits the flowers of a wide variety of plant species, both native and introduced. Although widespread, this species is not abundant at any one particular location. It has been hypothesised that human made nest sites can be used to increase its numbers.