ZIP 98601 falls in Clark County, Washington, where we hold 29,836 parcels measured as septic county-wide and 118,278 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 98601.
ZCTA 98601 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) |
|---|---|---|---|---|
| Clark County, Washington | 91% | — | 29,836 | 118,278 |
| Cowlitz County, Washington | 9% | 1 | 14,939 | 23,336 |
1 businesses on record with an address in this ZIP: pumping, installation, design, inspection and repair. Not an endorsement, and we take no fee.
| Company | City | Phone | Rating |
|---|---|---|---|
| Alltime Construction LLC | Amboy | (360) 949-5008 | — |
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 29,836 parcels measured as septic for Clark County, Washington as a whole, not broken out by ZIP.
ZIP 98601 spans 2 counties: Clark County, Washington, Cowlitz County, Washington.