ZIP 77581 falls in Brazoria County, Texas, where we hold 27,040 parcels measured as septic county-wide and 130,065 on sewer. We do not have a per-ZIP parcel count for this county, so this is the county total, not a count specific to ZIP 77581.
ZCTA 77581 is not entirely inside one county. Land-area share is from the 2020 Census ZCTA-to-county relationship file.
| County | Land in this ZIP | Documents held | On septic (county) | On sewer (county) |
|---|---|---|---|---|
| Brazoria County, Texas | 94% | — | 27,040 | 130,065 |
| Harris County, Texas | 6% | — | 128,872 | 1,412,534 |
Land-area overlap is from the 2020 Census Bureau ZCTA5-to-county relationship file, not an estimate of ours. Parcel and document counts are rows we hold, not a survey of every property in the ZIP. Last verified 2026-09-01.
We hold 27,040 parcels measured as septic for Brazoria County, Texas as a whole, not broken out by ZIP.
ZIP 77581 spans 2 counties: Brazoria County, Texas, Harris County, Texas.