National ZIP Code Crosswalk, [United States], 1990-2020

The datasets in this study allow researchers to accurately link ZIP Codes with characteristics of the populations they represent. This data collection addresses the issue in longitudinal research related to changes in ZIP Code boundaries that occur between decennial censuses.

The data identify boundary changes among ZIP Codes from 1990 to 2020 and provide numeric codes that group ZIP Codes into the smallest consistent geographic units across each decade (1990–2000, 2000–2010, and 2010–2020). These groupings allow for reliable comparisons and analyses of ZIP Code–level data over time.

Access the National ZIP Code Crosswalk, [United States], 1990-2020 (ICPSR 39431) study page