In 2004, homeownership rates peaked in the United States with home prices peaking 2 years later in 2006. Since these peaks, homeownership rates and home prices have fallen at the national level. In the current housing market downturn, it is crucial that researchers have accurate mortgage data to document changes over time. Two longitudinal surveys conducted by the U.S. Census Bureau collect mortgage data. The American Housing Survey (AHS) follows housing units over time and collects information on the quality of housing in the United States, as well as information on household characteristics. The Survey of Income and Program Participation (SIPP) is a panel study of households. The main objective of the SIPP is to provide accurate and comprehensive information about income and program participation in the United States. To provide a baseline for analyzing housing unit and household mortgage data after the burst of the housing bubble, we analyze data on owner-occupied housing units and homeowners with a least one mortgage from the 2005 AHS and wave 3 of the 2004 SIPP panel. This paper documents (1) differences in mortgage questions asked in both surveys; (2) the magnitude of differences between mortgage items between the two surveys; and (3) the extent to which differences are due to sample and questionnaire differences.We examine data on the prevalence of fixed mortgages, adjustable rate mortgages, and government insured mortgages, as well as data on interest rates, mortgage terms, and levels of home equity. In addition to analyzing the differences between the surveys, we examine demographic, economic, and regional differences in mortgage characteristics. Our findings suggest that terms and interest rates for first and second mortgages are consistent across both surveys, that the AHS underrepresents the number of adjustable rate mortgages (ARMs), and that the SIPP overrepresents FHA and VA program participation on second mortgages. We conclude with suggestions for improving mortgage data on both surveys.