Knowledge of space use and territoriality of New World birds largely derives from studies in temperate North America and the tropics, whereas it remains poorly studied in temperate South America, particularly in arid environments. Here we studied the seasonal space use and territory size among resident individuals of three sparrows in a temperate semi-desert of Argentina: the ringed warbling-finch Poospiza torquata, the rufous-collared sparrow Zonotrichia capensis and the manycoloured Chaco-finch Saltatricula multicolor. Both territorial behaviour and use of space of the three species showed seasonal changes. The ringed warbling-finch and the rufous-collared sparrow used larger areas during the non-breeding season than during the breeding season, while the many-coloured Chaco-finch used areas of similar size in the two periods. Defence activities were absent for all three species during the non-breeding season. During the breeding season, each species defended territories that were smaller for the rufous-collared sparrow (0.79 ± 0.04 ha) than for the ringed warbling-finch (1.35 ± 0.04 ha) and the many-coloured Chaco-finch (1.21 ± 0.07 ha). Seasonal territoriality and territory size reported for resident individuals were similar to those reported for north-temperate sparrows in xeric environments.