Units that are classified as vacant for seasonal, recreational, or occasional use make up a class that is often referred to as “vacation” homes. These may be large summer estates on Long Island, time-sharing condos in Fort Lauderdale, or simple fishing cabins in northern Michigan. Analysts often use this category to estimate the number of second homes in a given area.

Florida was the clear leader in the number of these units over the last three censuses, but, before 1980, the clear leader was New York. On a percentage basis, the three northern New England states (Maine, New Hampshire, and Vermont) have been at the top since the first housing census in 1940 (see graph).

In order to make the vacation home category consistent over the decades, “seasonal”, “held for occasional use”, and “for migrant workers” are combined. The “occasional use” category was not used prior to the 1960 census, which could partly explain a surge in vacation housing in 1960. It is also true that the number of units recorded for this first-time classification in 1960 was very small. Counts of seasonal and occasional use vacant units are separately provided from 1960 to 1980, but they were combined beginning in 1990 because evidence indicated enumerators had great difficulty determining the difference.

Counts of housing units for migrant workers were included with seasonal units before 1990. For comparability, this housing type was added beginning with the 1990 count of seasonal, recreational, or occasional units. Separate counts of migratory vacant units are provided beginning with 1990, for data users who would like to exclude them from the count of vacation homes. The number of units for migrant workers has been very small over the decades.