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explainer · static approved data

ZIP-to-Metro Relationship Explainer

Inspect approved HUD ZIP-to-county and ZIP-to-CBSA relationships, including residential weights and honest ambiguity instead of neighborhood guesses.

Release h31-content-tools-2026-07-24-r2 Updated 2026-07-23 Review due 2026-10-23

What this tool does

Select only from ZIP codes already present in the approved static release. Residential weights show why a single-label answer can be misleading. Nothing entered here is sent to a provider or retained.

Narrow the approved rows

These controls filter data already embedded in this page. They make no provider request and are not recorded by analytics.

55 approved row(s) shown.

HUD USPS ZIP Code Crosswalk relationships
ZIP codeRelationshipGeography IDPostal city labelStateResidential weightMultiple relationships
02108cbsa14460BOSTONMA100.0000%No
02108county25025BOSTONMA100.0000%No
10001cbsa35620NEW YORKNY100.0000%No
10001county36061NEW YORKNY100.0000%No
20001cbsa47900WASHINGTONDC100.0000%No
20001county11001WASHINGTONDC100.0000%No
30303cbsa12060ATLANTAGA100.0000%No
30303county13121ATLANTAGA100.0000%No
33130cbsa33100MIAMIFL100.0000%No
33130county12086MIAMIFL100.0000%No
46312cbsa16980EAST CHICAGOIN100.0000%No
46312county18089EAST CHICAGOIN100.0000%No
46320cbsa16980HAMMONDIN100.0000%No
46320county18089HAMMONDIN100.0000%No
46368cbsa16980PORTAGEIN100.0000%No
46368county18089PORTAGEIN0.0051%Yes
46368county18127PORTAGEIN99.9949%Yes
46402cbsa16980GARYIN100.0000%No
46402county18089GARYIN100.0000%No
46802cbsa23060FORT WAYNEIN100.0000%No
46802county18003FORT WAYNEIN100.0000%No
60010cbsa16980BARRINGTONIL100.0000%No
60010county17031BARRINGTONIL41.7896%Yes
60010county17089BARRINGTONIL0.2566%Yes
60010county17097BARRINGTONIL52.7421%Yes
60010county17111BARRINGTONIL5.2117%Yes
60201cbsa16980EVANSTONIL100.0000%No
60201county17031EVANSTONIL100.0000%No
60409cbsa16980CALUMET CITYIL100.0000%No
60409county17031CALUMET CITYIL100.0000%No
60439cbsa16980LEMONTIL100.0000%No
60439county17031LEMONTIL92.3903%Yes
60439county17043LEMONTIL5.8438%Yes
60439county17197LEMONTIL1.7659%Yes
60527cbsa16980WILLOWBROOKIL100.0000%No
60527county17031WILLOWBROOKIL14.2103%Yes
60527county17043WILLOWBROOKIL85.7897%Yes
60601cbsa16980CHICAGOIL100.0000%No
60601county17031CHICAGOIL100.0000%No
60614cbsa16980CHICAGOIL100.0000%No
60614county17031CHICAGOIL100.0000%No
60647cbsa16980CHICAGOIL100.0000%No
60647county17031CHICAGOIL100.0000%No
75201cbsa19100DALLASTX100.0000%No
75201county48113DALLASTX100.0000%No
77002cbsa26420HOUSTONTX100.0000%No
77002county48201HOUSTONTX100.0000%No
80202cbsa19740DENVERCO100.0000%No
80202county08031DENVERCO100.0000%No
85004cbsa38060PHOENIXAZ100.0000%No
85004county04013PHOENIXAZ100.0000%No
90012cbsa31080LOS ANGELESCA100.0000%No
90012county06037LOS ANGELESCA100.0000%No
98101cbsa42660SEATTLEWA100.0000%No
98101county53033SEATTLEWA100.0000%No

Sources and method

The compiler resolved approved Research Packet v2 records against an immutable release. The page contains static rows and makes zero provider calls during ordinary use.