PlainZIP

Calumet, PA · standard

ZIP Code 15621

Westmoreland County, Pennsylvania - USPS delivery-area record. The Census publishes no ACS estimates for this ZIP, so no demographic or housing figures are shown.

47
2,826/sq mi High-density area

National ZIP placement

Calumet has 47 residents, placing it among the least populous of the 33,099 US ZIP codes with a reported population, at 2,826 people per square mile.

Source: USPS ZIP record + U.S. Census Bureau ZIP population. Rank compares ZIP 15621 against every US ZIP with a reported population; income/home-value percentiles are not available for this ZIP.

ZIP code 15621 is a sparsely populated ZIP (a standard USPS delivery area) in Calumet, Westmoreland County, Pennsylvania, home to just 47 residents across 0.0 square miles, a density of 2,826 people per square mile, in the New York time zone.

The Census withholds ACS estimates for many sub-100-resident and PO-box ZIPs; only the USPS delivery-area record is shown here.

This page carries no survey figures; where they exist on other ZIPs they come from the U.S. Census Bureau American Community Survey 5-Year Estimates (including median rent) and the FHFA House Price Index, no estimates, no proprietary scoring. Verify with Census →

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Source: U.S. Census Bureau, American Community Survey 5-Year Estimates + ZIP Code Business Patterns + FHFA HPI ACS demographics and median rent, ZBP business establishments, FHFA HPI for ZIP 15621, Calumet, PA · 2023 Census ACS 5-Year Estimates use a rolling 60-month sample for stable small-geography estimates; ZBP updated annually; FHFA HPI updated quarterly/annually.

Quick Facts

47

Population

0.0

Area (sq mi)

2,826

People / sq mi

New York

Time Zone

standard

ZIP Type

Nearby ZIP Codes

Want a side-by-side? Compare 15621 vs 15689 →

ZIP Code City Population Distance
15689 United, PA 229 0.7 mi
15676 Pleasant Unity, PA 437 2.1 mi
15616 Armbrust, PA 23 4.0 mi

Related Areas

Westmoreland County Calumet, PA Pennsylvania

Frequently Asked Questions

What county is ZIP code 15621 in?

ZIP code 15621 (Calumet) is located in Westmoreland County, Pennsylvania. Westmoreland County contains multiple ZIP codes, see the full list at /counties/westmoreland-pa.

What is the population of ZIP code 15621?

ZIP code 15621 in Calumet, PA has a population of 47 according to the Census Bureau ACS 2023 estimates.

Data sources

ZIP 15621's figures come from ACS 5-Year Estimates, Census ZIP Code Business Patterns, and the FHFA House Price Index. See our methodology for details.

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What to do with ZIP 15621's numbers, next.

ZIP Code Tabulation Areas (ZCTAs) are Census Bureau approximations of USPS ZIP codes; figures describe the ZCTA area, not any single address within it.

This page explains the source records, calculation, and limits behind the figures shown. ZIP-level Census records are displayed directly; county, state, and national comparisons are calculated from those published records. Read our editorial standards and corrections policy, the methodology behind these numbers, or report a correction. Data current as of 2026-08-25.