Some of the first questions asked in the decennial census are about how many people live in a household and their relationship to the head of that household. If there is no answer beyond “Person 1,” it is presumed that the person lives alone. According to the 2020 census, 37 million adults were living alone, up from 33 million in 2010. In 1960, the number was well under half of that. Today, the state where the most people live alone is North Dakota.

One factor in the increase of single-person households is the decline in the number of marriages nationwide. In 1950, the Census Bureau reported that 23% of persons aged 15 and over had never been married. By the 2020 census, that percentage had risen to 34%. Meanwhile, the median age of first-time marriage has risen, as has the rate of divorce.

To find the states where the most people live alone – that is, the states with the most single-person residences – 24/7 Tempo used U.S. Census Bureau data, ranking states by the share of non-family households out of all households. We added the share of people living alone as a percentage of the civilian, noninstitutionalized 16+ population. All other data, including median annual household income, monthly gross rent, and bachelor’s degree attainment rate, comes from the Census Bureau’s 2019 American Community Survey; numbers are estimates for that year, and both rent and income are expressed in 2019 inflation-adjusted dollars.

Click here to see the states where the most people live alone

In North Dakota, the No. 1 state on our list, almost 19% of adults live alone, comprising nearly 34% of households. This may be due in part to the state’s energy boom, which attracted young, single people from around the country. North Dakota also has relatively low rents, so the combination of economic opportunity and cheap housing may account for its top position among states. (This is the size of an average family in every state.)

At the other end of our list is Utah, where ljust over 8% of adults live alone, comprising 19% of households. That may have something to do with the state’s religious profile. Most residents are Mormon and are more likely to marry and to have more children. In California and Hawaii, the reason for their relatively few single-person residences could be economics. Both have some of the most expensive housing costs in the nation. (On the other hand, these are the cheapest cities where everybody wants to live right now.)