Grandidier's free-tailed bat (Mops leucogaster) is a species of bat in the family Molossidae.

It has at times been considered synonymous with the little free-tailed bat.

[2] A ring species occurs when two populations that are connected by a geographic ring of populations that can interbreed but do not interbreed despite living in the same region.

Upon migrating to the Comoros, Grandidier's free-tailed bat and C. pusillius became sympatric.

There is evidence of isolation between the two populations further restricting gene flow.