Poecilotheria smithi is a Critically Endangered Theraposid known only from the type locality Haragama in the Kandy District, Sri Lanka. It was thought to be distribution specific to Haragama. During a survey on the genus Poecilotheria, which was initiated in 2011 by the authors, P. smithi was recorded, the first confirmed observation of P. smithi outside of its type locality from the Matale district about 31.42 Km in aerial distance northwest of the type locality. Distribution of this species extended in Sri Lanka by this novel record. P. smithi displays the social behaviour of sharing same microhabitat with few individuals. As demonstrated for P. smithi, we suggest the large group size and social behaviour observed was in response to unavailability of suitable micro habitat for the mature individuals.