Census 2000 enumerated 105.5 million households in the United States, of which the majority (52 percent) were maintained by married couples (54.5 million). A reflection of changing life styles is mirrored in Census 2000’s enumeration of 5.5 million couples who were living together but who were not married, up from 3.2 million in 1990. These unmarried-partner households were self-identified on the census form as being maintained by people who were sharing living quarters and who also had a close personal relationship with each other. The majority of these unmarried-partner households had partners of the opposite sex (4.9 million) but about 1 in 9 (594,000) had partners of the same sex. Of these same-sex unmarried-partner households, 301,000 had male partners and 293,000 had female partners.

This report presents information from Census 2000 on the characteristics of the 60 million households maintained by couples (also called coupled households). These coupled households were assigned to 1 of 4 mutually exclusive groups, depending on the relationship and gender of the householder and the spouse or partner: opposite-sex married couples, opposite-sex unmarried partners, male same-sex unmarried partners, and female same-sex unmarried partners. The numbers in this report do not show a complete count of all married couples and unmarried partners but only of couples and partners where one person was the householder. If the household included more than one couple, the household designation was determined by the status of the householder. For example, if a household was maintained by an unmarried couple but also contained the son of the householder and the son’s wife, the household would be tabulated only as an unmarried-partner household in this report.

The information on household type is derived from the item on the Census 2000 questionnaire (Figure 1) that asked about the relationship of each person in the household to the person on line 1, the householder (the person in whose name the house was owned or rented). The relationship item, which has been asked on the census since 1880, provides information about both individuals and the make-up of families and households. In 1990, the category “unmarried partner” was added to the relationship item to measure the growing complexity of American households and the tendency for couples to live together before getting married.