Cortlandt ZIP Service Areas
Westchester County Health's Cortlandt population profile supplies the nine-ZIP regional service list below. It is the appropriate local starting list, but it is not a set of exclusive municipal polygons. Several entries also serve other regions, and the profile's geography should not be silently combined with a different county profile. For any particular Cortlandt parcel, verify the physical address through USPS and then use Town GIS or the Assessor to establish legal jurisdiction.
| ZIP | Areas covered | Postal association | Cortlandt research note |
|---|---|---|---|
| 10511 | Buchanan | Buchanan | Standard village ZIP; verify each street with USPS and municipal GIS. |
| 10517 | Crompond region | Crompond | Regional profile entry; post-office geography may not follow the Town boundary. |
| 10520 | Croton-on-Hudson | Croton-on-Hudson | Standard village ZIP that also serves other regions. |
| 10521 | Croton-on-Hudson | Croton-on-Hudson | PO Box and post-office association, not a parcel boundary. |
| 10547 | Mohegan Lake region | Mohegan Lake | Serves Cortlandt region and other areas; postal wording does not settle jurisdiction. |
| 10548 | Montrose and Cortlandt | Montrose | Standard ZIP; confirm the individual address. |
| 10562 | Regional service area | Ossining | Marked as serving other regions, so a boundary mismatch is possible. |
| 10567 | Cortlandt Manor area | Cortlandt Manor | Associated with Town Hall but can extend beyond a legal town boundary. |
| 10596 | Verplanck region | Verplanck | PO Box and post-office association; confirm the physical street address. |
Other online lists can mention nearby 10537, 10566, or 10598. The Town-specific research did not confirm those as Cortlandt-serving ZIPs, so they should not be added to a local list unless USPS verifies a specific address. This conservative approach avoids turning broad regional mailing data into a false municipal claim.
Check a Cortlandt ZIP Before Searching
A Cortlandt ZIP code directory works best after an address-level postal check. The USPS ZIP Code Lookup can search from a physical address, return ZIPs for a city and state query, or return cities associated with a ZIP. USPS also states that a returned ZIP does not confirm that a person or company is at an address. Use it to confirm postal routing, not occupancy or ownership.
That distinction matters in Cortlandt because the Town includes village, hamlet, and neighboring-city address language. The Town FAQ associates Cortlandt Manor, Buchanan, Montrose, Croton-on-Hudson, Verplanck, and selected Mohegan Lake and Crompond streets with Cortlandt residency contexts. Each label can be useful for postal searching, yet only the parcel and municipal map resolve the legal custodian. A service ZIP may cross those lines.
Note: A USPS result confirms postal routing for an address, while Cortlandt map and parcel records identify the relevant local jurisdiction.
Cortlandt Postal Lookup Fields
The USPS tool captured in research has separate search modes. The By Address tab is the right route for a physical Cortlandt address. By City and State returns ZIPs associated with a place query, while Cities by ZIP performs the reverse look-up. An apartment or suite can refine a postal result, but the tool still answers a routing question rather than a property or person question.
| USPS field or mode | Type | Required | Use |
|---|---|---|---|
| By Address | Tab | No | Address-to-ZIP mode. |
| Street Address | Text | Yes | Physical street address. |
| Company | Text | No | Optional. |
| Apt/Suite/Other | Text | No | Optional secondary designator. |
| City | Text | Yes | Postal city or place. |
| State | Select | Yes | State selector. |
| ZIP Code | Text | No | Optional refinement. |
| By City and State | Tab | No | Returns ZIPs for a city and state query. |
| Cities by ZIP | Tab | ZIP required | Reverse ZIP-to-city mode. |
USPS does not expose a direct current municipal-boundary polygon in this research. When a result must be connected to a Cortlandt parcel, use the postal result as a lead and compare it with the Town GIS and property route rather than treating it as a final boundary answer.
Find Cortlandt Residents by ZIP
For a named Cortlandt resident, use ZIP data as one matching detail in a narrow official check. The New York voter lookup asks for county, last name, first name, date of birth in the displayed format, ZIP Code, and address information. It is a cookie- and JavaScript-dependent verification form. Select Westchester County, use the ZIP associated with the physical address, and test the village or postal-place wording when an address is in Buchanan or Croton-on-Hudson.
- Confirm the address and ZIP in the USPS tool, recording the postal city it returns.
- Check the parcel's municipality with the Town GIS or the Assessor, especially near a village or Peekskill boundary.
- For a named registration question, enter the required details in the New York voter lookup and use the ZIP as one form field.
- If the form fails or the address is confidential, contact the Westchester County Board of Elections instead of repeatedly trying name variants.
- Once a ZIP has narrowed the area, use the address-based Cortlandt street directory for the parcel, map, and deed sequence.
The state form is not a downloadable ZIP-wide roster. New York election records also exclude protected identifiers, and confidential registration can restrict what is displayed. County GIS may show an election-district polygon, but the district is an administrative area, not a list of everyone at every address.
Cortlandt ZIPs and Legal Lines
Postal geography and legal geography overlap without being the same thing. A situs address is the parcel's physical location. A mailing address is where a tax bill or other mail is sent. A postal city is the place name used by mail delivery. The legal municipality identifies the town, village, or city that governs the parcel. In Cortlandt, each of those terms can differ on the same record trail.
ZIP 10520 and 10521 illustrate a local postal distinction: one is a standard Croton-on-Hudson ZIP association and the other is a PO Box or post-office association. The regional profile also flags 10517, 10547, and 10562 as serving other regions. These are useful starting points, not proof that a given address is within Cortlandt. Start municipal confirmation with Town GIS and the Assessor's address or owner-name route.
- ZIP versus ZIP+4
- A ZIP identifies a broad postal delivery area; ZIP+4 adds a more specific delivery segment.
- PO Box ZIP
- A ZIP associated with post-office boxes. It is not a physical service-area boundary.
- Unique ZIP
- A ZIP assigned to a single organization or delivery arrangement. None is asserted for Cortlandt here.
- Carrier route
- A mail-delivery sequence used for routing. It does not establish a legal municipality or household presence.
Note: Write the postal city and legal municipality in separate notes whenever an address could cross a Cortlandt, village, city, or county boundary.
Cortlandt ZIP Record Limits
Several official systems accept a ZIP Code, but their purpose changes what the result means. New York's public voter form uses ZIP with name, county, date of birth, and address information. The state public registry has a ZIP-only mode within its statutory disclosure limits. The Comptroller's unclaimed-funds search accepts city and ZIP, and Westchester trade-license searches can use city, state, and ZIP. None turns a ZIP into proof of residence or a general list of people.
The Town's CAI property search and GIS may be useful after a ZIP narrows a physical address, but research did not capture live ZIP-field behavior for those tools. Do not assume a ZIP filter exists there. Use the verified address and parcel routes instead. For a request to an office, provide the known address, date range, record type, and preferred format rather than asking for a newly created ZIP report.
Once a postal check and map identify a Town parcel, the current CAI Property Card is the property route. The Town says it carries current owner, transfer, and mailing categories, while GIS property record cards became static or historic after June 1, 2024. That distinction keeps a ZIP-based search tied to the current Cortlandt source.
Cortlandt Voter ZIP Checks
The state voter tool is the official online verification channel. It does not replace the Westchester County Board of Elections, which is at 25 Quarropas Street in White Plains and publishes 9:00 a.m. to 5:00 p.m. filing hours in county election material. For a confidential address or a failed form, the Board is the next route. Election Law §3-220 makes voter-registration records public under supervision while excluding driver-license, non-driver ID, Social Security, and facsimile numbers.
A defined voter-data request has separate limits. The state Board of Elections says a request for voter-registration data must state an elections purpose under Election Law §3-103(5). It is not an address directory request. New York's confidential-registration procedures also protect eligible people. Treat a blank result as an unresolved verification question, not as evidence about the person or parcel.
Note: Record the date and exact postal wording used for any Cortlandt voter verification, because an address can have village and postal variants.
Cortlandt ZIP History Clues
Postal history can occasionally clarify an older place reference. The USPS historical postmaster tool searches by the first three ZIP digits and returns ZIP, post office, state, and established and discontinued dates. USPS warns that the information may no longer be current. It is a historical post-office lead, not a present parcel map.
For Cortlandt land history, the more useful follow-up remains the parcel, legal description, and recorded deed route. County historical maps, the 1868 Beers atlas, and local directories can place an older road or community name, while USPS can only help explain a postal association. Keeping those layers separate makes ZIP research more accurate and avoids attributing a regional mailing label to the wrong municipality.
New York's ZIP and county FIPS cross-reference, using a government geographic code, is a dated crosswalk rather than a current USPS polygon. Its captured source table includes 10511 and 10548, which makes it a useful historical comparison but not a substitute for an address-level Cortlandt check.