Bangladesh, Bhutan, China (mainland), India, Laos (B), Myanmar, Nepal, Thailand, Vietnam.
Eastern Himalayas from central Nepal east to north-eastern India (eastern Arunachal Pradesh) and neighbouring parts of northern Myanmar and southern China (southern Yunnan); also Nagaland south to Mizoram and Meghalaya (north-eastern India), and Laos and Vietnam.
 
Population
Estimated population is unknown (2010).
Grey-cheeked Warbler (Phylloscopus poliogenys) [XC797106]
by id from Phou Sam Soum, Xiangkhouang, Laos (call)
Grey-cheeked Warbler (Phylloscopus poliogenys) [XC426892]
by Chubzang, bhutanbirdingtours.com from Eagle Nest, Bompu camp area, Arrunachal Pradesh, India (song)
Subspecies
No subspecies.
Analyses of mitochondrial DNA suggest that this and White-spectacled Warbler (Phylloscopus intermedius) are sister-species, and that they form a clade together with Green-crowned Warbler (Phylloscopus burkii) and Grey-crowned Warbler (Phylloscopus tephrocephalus). Mitochondrial DNA further indicates that Himalayan populations may be specifically distinct from Yunnan (China) and southern Vietnam populations (the two latter are also well differentiated). Further research is required.