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State markets/Texas/Caldwell County/ZIP area 78666

ZIP AREA · ZCTA 78666 · CENSUS 2020

ZIP area 78666

The 27 census tracts that make up ZIP Code Tabulation Area 78666 across 4 counties. Each tract opens its own lender ranking and its full HMDA record list.

Census tracts

27

18 counted under this ZIP

Counties

4

this ZIP crosses a county line

Population

80,338

of the tracts this ZIP owns

Owner-occupied units

9,846

17,772 1-4 family homes

Census tracts in ZIP area 78666

Every tract this ZIP area touches — sort, filter by population or overlap, export, or open a row for the tract's card. The RECORDS column opens that tract's HMDA records in the loan explorer, which is where a ZIP-scoped question becomes an exact one.

27 OF 27 TRACTSEVERY TRACT THIS ZIP AREA TOUCHES — NO ROWS WITHHELD
RECORDS
Caldwell County78655This tract overlaps 78666 but sits mostly inside 78655, so it is counted there and not here.17.0%4,201ModerateOPEN →
Comal County78133This tract overlaps 78666 but sits mostly inside 78133, so it is counted there and not here.4.4%3,381MiddleOPEN →
Comal County78132This tract overlaps 78666 but sits mostly inside 78132, so it is counted there and not here.20.0%7,241UpperOPEN →
Comal County78130This tract overlaps 78666 but sits mostly inside 78130, so it is counted there and not here.1.8%8,822MiddleOPEN →
Guadalupe County78666Most of this tract's land is inside 78666, so its population and housing count toward 78666.77.0%4,823ModerateOPEN →
Guadalupe County78638This tract overlaps 78666 but sits mostly inside 78638, so it is counted there and not here.10.2%3,131MiddleOPEN →
Guadalupe County78155This tract overlaps 78666 but sits mostly inside 78155, so it is counted there and not here.14.7%3,081MiddleOPEN →
Hays County78666Most of this tract's land is inside 78666, so its population and housing count toward 78666.100.0%2,809MiddleOPEN →
Hays County78666Most of this tract's land is inside 78666, so its population and housing count toward 78666.100.0%6,908—OPEN →
Hays County78666Most of this tract's land is inside 78666, so its population and housing count toward 78666.100.0%4,956LowOPEN →
Hays County78666Most of this tract's land is inside 78666, so its population and housing count toward 78666.100.0%5,983LowOPEN →
Hays County78666Most of this tract's land is inside 78666, so its population and housing count toward 78666.85.7%4,273LowOPEN →
Hays County78666Most of this tract's land is inside 78666, so its population and housing count toward 78666.100.0%2,337—OPEN →
Hays County78666Most of this tract's land is inside 78666, so its population and housing count toward 78666.100.0%1,960LowOPEN →
Hays County78666Most of this tract's land is inside 78666, so its population and housing count toward 78666.100.0%6,041LowOPEN →
Hays County78666Most of this tract's land is inside 78666, so its population and housing count toward 78666.100.0%3,914LowOPEN →
Hays County78666Most of this tract's land is inside 78666, so its population and housing count toward 78666.97.8%7,672ModerateOPEN →
Hays County78666Most of this tract's land is inside 78666, so its population and housing count toward 78666.100.0%4,343ModerateOPEN →
Hays County78666Most of this tract's land is inside 78666, so its population and housing count toward 78666.100.0%3,584ModerateOPEN →
Hays County78666Most of this tract's land is inside 78666, so its population and housing count toward 78666.100.0%5,271MiddleOPEN →
Hays County78666Most of this tract's land is inside 78666, so its population and housing count toward 78666.100.0%4,055MiddleOPEN →
Hays County78666Most of this tract's land is inside 78666, so its population and housing count toward 78666.100.0%3,354MiddleOPEN →
Hays County78666Most of this tract's land is inside 78666, so its population and housing count toward 78666.100.0%5,707ModerateOPEN →
Hays County78666Most of this tract's land is inside 78666, so its population and housing count toward 78666.100.0%2,348ModerateOPEN →
Hays County78676This tract overlaps 78666 but sits mostly inside 78676, so it is counted there and not here.36.5%3,011MiddleOPEN →
Hays County78676This tract overlaps 78666 but sits mostly inside 78676, so it is counted there and not here.13.9%5,494UpperOPEN →
Hays County78676This tract overlaps 78666 but sits mostly inside 78676, so it is counted there and not here.3.1%10,047MiddleOPEN →

Counties this ZIP area crosses

A ZCTA is drawn from address geography, not county lines, so a ZIP can and often does span two or more counties. 10,186 of the 33,791 ZCTAs do.

What a ZIP area is, and what it is not

A ZCTA — ZIP Code Tabulation Area — is the U.S. Census Bureau's area approximation of a USPS ZIP code, not the ZIP code itself. HMDA reports no postal geography at all, so these rows are census tracts grouped by the Census 2020 tract-to-ZCTA relationship file: each tract is counted once, in the single ZCTA covering the most of its land.

We publish no ZIP-level lending figure on this page, and the omission is deliberate. Summing tract originations into a ZIP would be an approximation dressed as a measurement: the boundary is areal, a tract that straddles two ZIPs has to be given to one of them, and HMDA never said the loan was in a ZIP in the first place. The lending figures live one level down, on each tract’s own page, where they are exactly what the lender reported.

Also checked and not used: FHA endorsement records carry a property ZIP, but they cover one loan programme rather than the market, and matching them to a county by name collides in Virginia, where “Richmond” is both a county and an independent city. We do not publish a figure we cannot attribute with certainty.

Go deeper

Step back up to the Caldwell County market profile, which lists every ZIP area in the county, or the Texas state profile.

Sources: U.S. Census Bureau 2020 ZCTA-to-census-tract relationship file (zcta_tract_rel, 168,212 overlaps across 33,791 ZCTAs and 85,143 tracts, loaded 2026-08-02); FFIEC census-tract file; HMDA tract attributes. Housing figures are summed over the tracts this ZIP area is dominant for, so they match the county page’s row for the same ZIP exactly. Figures are as loaded — see data attribution.