Bhutan (R), Cambodia, China (mainland) (R), Denmark (P), Germany, Hong Kong (China), India (R), Iran [Islamic Republic of], Japan, Kazakhstan (R), Kuwait (NB) (P), Kyrgyzstan (R), Laos, Latvia, Malaysia, Mongolia (R), Myanmar, Nepal (R), North Korea, Pakistan (R), Poland, Russia (Asian) (R), Russia (Central Asian) (R), Russia (European) (R), Singapore, South Korea, Taiwan (China), Thailand, Vietnam.
Vagrant to Algeria, Austria, Belgium, Bulgaria, Cyprus, Czech Republic, Egypt, Estonia, Faroe Islands, Finland, France, Gibraltar, Greece, Hungary, Iceland, Indonesia, Israel, Italy, Libyan Arab Jamahiriya, Luxembourg, Malta, Morocco, Netherlands, Norway, Oman (NB), Portugal, Saudi Arabia (NB), Slovakia (Slovak Republic), Slovenia, Spain, Sweden, Switzerland, Turkey, United Arab Emirates (NB), United Kingdom.
Breeds northern Russia from middle and upper R Pechora and Urals east to eastern Siberia (R Anadyr region and Sea of Okhotsk), south to north-eastern Altai, north-western Mongolia, Baikal Mts and north-eastern China; non-breeding north-eastern Indian Subcontinent east to south-eastern Asia and Taiwan.
 
Population
Estimated population is unknown (2010).
Phylloscopus inornatus (Sibley and Monroe 1990, 1993) has been split into Inornate Warbler (Phylloscopus inornatus) and Hume's Leaf-Warbler (Phylloscopus humei) following AERC TAC (2003) (see Sangster et al. 2002).
Considered by some authors to be a subspecies of Yellow-breasted Warbler (Phylloscopus montis).
The Reader's Digest Book of British Birds 1980, 3rd Edition, Drive Publications Ltd ISBN 0 340 25308 8
Birds in Colour Campbell, B., 1960, Penguin Books Ltd
The Pocket Guide to Nest and Eggs Fitter, R.S.R., 1954, Collins
RSPB Handbook of British Birds Holden, P., Cleeves, T., 2002, A & C Black ISBN 0 7136 5713 8
Birds of Britain and Europe Sterry, P., et al., 2001, AA Publishing ISBN 0 7495 3068 5
The Popular Handbook of British Birds Hollom, P.A.D., 1973, H.F. & G. Witherby Ltd ISBN 0 85493 002 7