Since 1999, the University of Yangon and the Harrison Institute have conducted a series of bat surveys in Myanmar. During this time, six species of vespertilionid bat have been collected that have not been recorded previously from the country. Two, Myotis horsfieldi and Myotis chinensis were published in 2001 and one, Kerivoula kachinensis, which is a new species to science, in 2004. The remaining three, Myotis mystacinus, Ia io and Pipistrellus pulveratus are included here for the first time. The record of M. mystacinus is the first authenticated one for South-East Asia. Since small vespertilionid bats are difficult to identify and are generally poorly understood, the paper includes a brief review of all 24 species of Myotis, Ia, Pipistrellus, Hypsugo, and Arielulus currently listed for Myanmar. Three of these, Myotis annectans, Pipistrellus pipistrellus and Hypsugo savii are removed from the faunal list for lack of supporting data or because of previous misidentifications. The taxon Pipistrellus peguensis is included in the synonymy of Pipistrellus javanicus. The status of Pipistrellus anthonyi is discussed. Ninety-five species of bat, including forty-three species of vespertilionid, are now recorded from the country.