ZIP 21912 falls in Cecil County, Maryland, where we hold 32 septic-related documents. We have not classified septic-versus-sewer status for this county, and we do not have a per-ZIP parcel count -- see the county page for what we hold and where the records are kept.
ZCTA 21912 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) |
|---|---|---|---|---|
| Cecil County, Maryland | 100% | 32 | — | — |
| New Castle County, Delaware | 0% | 5,964 | — | — |
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 have not measured septic-versus-sewer status for this county yet.
ZIP 21912 spans 2 counties: Cecil County, Maryland, New Castle County, Delaware.