In which county is ZIP code 21104 located?

ZIP 21104 is listed under Carroll, MD.

When was this page updated?

This page was updated on 2026-01-08.

ZIP Code 21104: Marriottsville, MD

ZIP: 21104

County: Carroll

Coordinates: 39.33420, -76.91320

ZIP Type: Standard

Time Zone: Eastern Time (ET)

This profile provides an in-depth look at ZIP code 21104, serving Marriottsville in MD. It lies in Carroll and supports delivery, planning, and address verification.

Primary City	Marriottsville
ZIP Code	21104
County	Carroll
State	MD
Latitude / Longitude	39.33420, -76.91320
ZIP Type	Standard
Time Zone	Eastern Time (ET)
Data Updated	2026-01-08

Maps & Useful Links

Open in Maps: Google Maps · OpenStreetMap

These links show the approximate center point for ZIP 21104 (not an exact boundary).

Geographic & Administrative Context

The geographic center of ZIP code 21104 is approximately 39.33420 (latitude) and -76.91320 (longitude). This location sits within Carroll, contributing to regional planning across MD.

Local Coverage Notes

ZIP codes can cover multiple neighborhoods and unincorporated areas. Use ZIP 21104 for mail delivery and general location reference in Carroll, MD.

Coverage may include nearby neighborhoods and adjacent unincorporated areas commonly associated with Marriottsville.

Related ZIP Codes (Nearby)

Explore other postal codes near Marriottsville within MD.

Frequently Asked Questions

What is the primary city for ZIP code 21104?

The primary city for this ZIP code is Marriottsville, located in MD.

In which county is 21104 located?

ZIP code 21104 is situated within Carroll, MD.

What are the coordinates for 21104?

The approximate center point is 39.33420 (Latitude) and -76.91320 (Longitude).

Is ZIP code 21104 active?

This page lists ZIP 21104 as Listed based on the latest refresh date shown above.

Does ZIP 21104 cover multiple areas?

Yes. Many ZIP codes cover multiple neighborhoods or nearby areas. For exact boundaries, use official mapping tools.

Methodology & Data Notes

How we build this page: We generate this page from a structured ZIP dataset and refresh key fields (city, county, and coordinates) during scheduled updates. Coordinates represent an approximate center point, not an official boundary map.
Sources: Public ZIP reference datasets and geographic coordinate references. If you use specific sources (e.g., USPS, Census), list them on your About/Methodology page.

Page updated: 2026-01-08