At the end of 2018, the 39,494 household-dwellings (later: households) with a head i.e. a reference person with foreign background in Helsinki made up 11.8 per cent of all households in the city. The reference person of a household is primarily the person in a household with the highest income, meaning that other persons in the household may have a Finnish background. In the following statistics, the origin of the reference person determines the origin of the whole household. The largest group of households with foreign background was those with Russia (or the former Soviet Union) as their background country, making more than one fifth (22 per cent) of all households with foreign background, followed by Estonian households with a 13 per cent share and Somali households with a 7 per cent share.

Households with foreign background are, on average, larger than households with Finnish background. One-person households accounted for 36 per cent of the former and half of the latter of the total number of households. Furthermore, 9 per cent of households with foreign background were composed of five or more people while only about 2 per cent of households with Finnish background were that size.