What county is Katy, TX in?
Updated · Data: U.S. Census Bureau
Katy, Texas is in 3 counties. Most residents (53.8%) live in the Harris County part; the rest live in Fort Bend County and Waller County.
Which counties do Katy residents live in?
| County | Share of residents | Chart |
|---|---|---|
| Harris County | 53.8% (12,855 people) | |
| Fort Bend County | 25.5% (6,092 people) | |
| Waller County | 20.7% (4,953 people) |
How is Katy's land split between counties?
| County | Share of land area | Chart |
|---|---|---|
| Waller County | 36.7% | |
| Harris County | 33.9% | |
| Fort Bend County | 29.5% |
Most of Katy's land is in Waller County, but most of its people live in Harris County. Which county you are in depends on your street.
Inside Katy, the county depends on the address: check your address privately. See all Texas cities in more than one county or look up another city.
Katy at a glance
What ZIP codes are in Katy?
6 ZIP codes use the name Katy or are centered in it. Shares are of each ZIP's land; a ZIP named after a town can reach beyond its city limits.
| ZIP | Post office name | County (land share) |
|---|---|---|
| 77449 | Katy | Harris County |
| 77450 | Katy | Harris County 66%, Fort Bend County 34% |
| 77491 | Katy | Fort Bend County |
| 77492 | Katy | Fort Bend County |
| 77493 | Katy | Harris County 68%, Waller County 32% |
| 77494 | Katy | Fort Bend County 85%, Waller County 8%, Harris County 7% |
About Harris County
County seat: Houston. FIPS code 48201. Population 4,758,579. All Harris County facts.
Towns near Katy
- Cinco Ranch: 6.0 mi away, Fort Bend County
- Brookshire: 6.7 mi away, Waller County
- Fulshear: 7.3 mi away, Fort Bend County
- Weston Lakes: 11 mi away, Fort Bend County
- Simonton: 11 mi away, Fort Bend County
- Mission Bend: 12 mi away, Fort Bend County
Katy has about 23,900 people. It is an incorporated city or town.
Sources: ACS 2019-2023 5-year (residents by county, table B01003); Census TIGER/Line 2024 and Gazetteer 2024 (land, location); Census 2020 ZCTA file and GeoNames (ZIP codes). Data as of November 1, 2026. Not affiliated with any government agency.
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What county is Katy, TX in?
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