A housing unit is owner-occupied if the owner or co-owner lives in the unit, even if it is mortgaged or not fully paid for. The unit is defined as such: "Owned by you or someone in this household with a mortgage or loan" if it is being purchased with a mortgage or some other debt arrangement such as a deed of trust, trust deed, contract to purchase, land contract, or purchase agreement.

The unit is also considered owned with a mortgage if it is built on leased land and there is a mortgage on the unit. Although owner-occupied units are divided between mortgaged and owned free and clear on the questionnaire, census data products containing 100 percent data show only total owner-occupied counts.

U.S. Census, Census of Population and Housing, 1990: Summary Tape File 3 Technical Documentation / prepared by the Bureau of the Census-Washington: The Bureau [producer and distributor], 1992.