Variation in communicative skills, defined as gestures, vocabulary comprehension and vocabulary production, was examined as a function of gender, birth order, childcare and socioeconomic status (SES) in 1,019 18-month-old children. The children were recruited at their regular check-up at a number of randomly selected Child Health Care centers in a Swedish county. The participation rate was 88%. The children were assessed by their mothers using a short version of the Swedish Early Communicative Development Inventories. The results demonstrate significant effects of gender and birth order on vocabulary comprehension and vocabulary production. Girls scored higher than boys and first-born children scored higher than later-born children. Type of childcare (family care, care at home and day-care centers) interacted with gender and birth order on vocabulary production and indicated that family care is not as advantageous as care at home or at day-care centers. SES had no effect on children's communicative skills at this age.