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The best U.S. states for multigenerational living — and the worst

Many American houses aren't built to hold three generations. HouseCanary ranks the best and worst states for multigenerational living

Michael Tuszynski / Unsplash

More families are sharing a home across generations than they were a decade ago. Grandparents move in to help with child care. Adult children stay home longer to save for a place of their own. Aging parents need somewhere safe to land when living alone stops working. Each of these situations asks the same basic question of a house. Does it have room for everyone, and can the household afford the space it needs without stretching every paycheck to the breaking point.

The answer depends on how a state's homes were built, not just how much they cost. A four-bedroom house solves a lot of problems that a three-bedroom house can't, and a finished basement can add a bedroom, a living area, or a small apartment without the cost of an addition. Nationally, though, those features remain scarce. Fewer than one in four homes nationwide has four or more bedrooms, and fewer than one in three includes a basement at all. Where a family lands within that mix can mean the difference between converting existing space and paying a steep premium to buy a bigger house outright.

HouseCanary built a Multigenerational Living Index that scores every state on the share of homes with four or more bedrooms, the share with basements, and how much more a bigger home costs relative to a smaller one. States that pair spacious layouts with contained price premiums make room for extended family without punishing the household. States without that housing stock leave families choosing between overcrowding, a steep premium, or giving up on the idea altogether. Here are the three states that do this best, and the three that do it worst.

Michael Tuszynski / Unsplash

Utah tops HouseCanary's Multigenerational Living Index because its housing stock already looks built for more than one family. Forty-one percent of Utah homes have four or more bedrooms, nearly double the national rate of 23%, and 53% of properties include a basement that a household can finish or convert into extra living space. That combination gives families room to expand without necessarily buying a different house.

A four-bedroom home in Utah costs about 1.39 times as much as a smaller home, well below the national average premium of roughly 1.6 times. HouseCanary credits that gap to a housing market where large homes and basements are common enough that builders and sellers haven't been able to charge the steep markup found in states where big houses are rare. For a family weighing whether to buy a bigger home outright or convert a basement into a bedroom, both options in Utah cost less than they would almost anywhere else. That 1.39 times premium is close to the lowest HouseCanary recorded anywhere in the country, a sharp contrast to the roughly 1.85 to 1.86 times premium families face in Arkansas, Mississippi, and Louisiana for the same jump in bedroom count.

Utah's strength extends across the Mountain West. Colorado, Idaho, and Wyoming all land in the top five on HouseCanary's index alongside Utah, each beating the national benchmarks for both........

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