This article examines differences in birth outcomes by neighbourhood income and recent immigration for singleton live births in Toronto, Ontario. The birth data were extracted from hospital discharge abstracts compiled by the Canadian Institute for Health Information. A population-based cross-sectional study of 143,030 singleton live births to mothers residing in Toronto, Ontario from 1 April 1996 through 31 March 2001 was conducted. Neighbourhood income quintiles of births were constructed after ranking census tracts according to the proportion of their population below Statistics Canada's low-income cutoffs. Logistic regression was used to estimate odds ratios for the effects of neighbourhood income quintile and recent immigration on preterm birth, low birthweight and full-term low birthweight, adjusted for infant sex and maternal age. Low neighbourhood income was associated with a moderately higher risk of preterm birth, low birthweight, and full-term low birthweight. The neighbourhood income gradient was less pronounced among recent immigrants compared with longer-term residents. Recent immigration was associated with a lower risk of preterm birth, but a higher risk of low birthweight and full-term low birthweight.