Moltoni's warbler is similar to the Western subalpine warbler. In the males the underparts in Moltoni's warbler are salmon pink while that of the Western subalpine warbler are orange. The females and juveniles are almost identical to those of the Western subalpine warbler. The main difference is vocalisations with the song of Moltoni's warbler being described as being faster paced and higher pitched than that of Western subalpine warbler, making a sound that is a rapid succession of insect-like notes, with the normal dry "trill zerr" call included in the song.