Lasius mixtus workers are small and yellowish. The petiole is low with an emarginate dorsal border. There are no standing hairs on scapes or front tibia and body hairs are shorter than L. flavus (Fabricius). Queens are brownish black with head about as broad as alitrunk. Males are brownish black with weakly dentated mandibles.
Throughout the British Isles.
It occurs throughout north Eurasia and Central Europe.