Corn Bunting Bird is an unspectacular sparrow-like bird, but conspicuous in its behaviour and often seen singing from wires and posts. The plumage is uniform and subtle, lacking outstanding features, and the sexes are similar. The crown and mantle are uniform brown with blackish-brown streaks, the rump is plainer and the wing feathers are dark-brown edged with pale buff. The tail is uniformly dark brown, lacking white in the outer tail feathers - unlike any of its close relatives. The underparts are buffish-white, the breast and flanks are clearly streaked blackish-brown, with the denser blacker streaks on the upper breast sometimes forming a 'V'-shaped gorget, joined by dark malar stripes that enclose a whitish-buff throat. Its bill is horn-coloured with a dark culmen, and looks large and bulky with a pronounced jagged outline to cutting edges. In flight the legs are frequently dangled.
Corn Bunting Bird is resident across much of the region, although in rapid decline across north-western Europe, and absent from Scandinavia. Corn Bunting Bird favours lowland or rolling open country, and is typically found in farmland and arable country, pastures, grasslands and rough open areas, generally away from woodland and tall hedgerows and with a liking for coastal areas. Males are polygamous.
The song of Corn Bunting Bird is frequently likened to the jangling of a bunch of keys, and is delivered by the male in spring and summer from a prominent perch such as a wire or post, and quite often from the top of a tall plant among the crops and grasslands that it favours. The song phrase accelerates and rises in pitch, beginning slowly and then quickly accelerating to a discordant crash of notes, typically of 1.5-2 seconds in length, as in "chutchit'it'it'tr'r'r'r'r' schri'i'i'i'i'i'eeee". The call notes are an abrupt yet soft "quit", "plic" or "bt", often delivered in flight and occasionally run together as "plic'plc 'plc'plc", and also a sharp "tsritt" or "chip".