Residential delivery area · Pennsylvania
ZIP Code 18104: Allentown, PA
ZIP code 18104 uses the postal name Allentown, Pennsylvania and lies entirely in Lehigh County (Census 2020 ZIP-county file). About 49,000 people live there (Census Bureau, ACS 2020-2024), the 3rd most populous of Allentown's 7 residential ZIP codes. Median household income is $94,601 (Census Bureau, ACS 2020-2024). By Census place, its land lies in Allentown (17%) and Cetronia (4%), and 3% in smaller places; 77% is outside any Census place.
- ACS2020-24
- Census2020
- FHFA2025
- ZBP2023
- IRS2022
- Town
- Allentown · 7 residential ZIPs
- County
- Lehigh County
- Census places
- Allentown (17%); Cetronia (4%) census-designated place
- Neighborhoods
- Griesemersville, Hilltown GeoNames
- Metro area
- Allentown-Bethlehem-Easton, PA-NJ
- House district
- PA-7 119th Congress
- State
- Pennsylvania
- Time zone
- Eastern
- Land area
- 23.0 sq mi · 2,121 people per sq mi
- PO Box ZIPs
- 18105 also use the name Allentown
Where is ZIP code 18104?
18104 centers on 40.612°, -75.547° and covers 23.0 square miles of land plus 0.2 of water. It borders 7 ZIP codes: 18106, 18069, 18102, 18052, 18103, 18037, 18078.
The map draws ZIP code areas only. For the streets inside 18104, open its center on OpenStreetMap.
Source: U.S. Census Bureau, 2020 ZCTA cartographic boundaries and the 2023 Gazetteer (2020 ZCTAs); ZIP-to-county shares, Census places and House districts (119th Congress) from the Census 2020 relationship files (shares of land); metro area from the OMB delineation (July 2023); town name and time zone from simplemaps US ZIP Codes (CC BY 4.0); neighborhoods from the GeoNames gazetteer (CC BY 4.0), placed in this ZIP code by PlainZIP.
How does 18104 compare with the rest of Allentown?
| Measure | 18104 | In Allentown | In Lehigh County | In PA |
|---|---|---|---|---|
| People (ACS 2020-2024) | 48,683 | 3rd of 7 | 3rd of 35 | 27th of 1,833 |
| Median household income | $95k | 1st of 6 | 12th of 27 | 230th of 1,015 |
| Median home value | $336k | 2nd of 5 | 11th of 28 | 193rd of 1,069 |
Its median household income is higher than in 77% of U.S. residential ZIP codes, and it is denser than 85% of all U.S. residential ZIP codes. ZIP codes at the ACS caps ($250,000 or more for household income, $2,000,000 or more for home value) share the top rank.
Source: U.S. Census Bureau, ACS 2020-2024 5-year estimates (B01003, B19013, B25077); ranks by PlainZIP over residential ZIP codes (ZCTAs).
How many people live in 18104?
The 2020 Census counted 47,289 people in 18104; the ACS, which samples households over 2020-2024, estimates 48,683. Between the 2010 and 2020 censuses its population grew 9.4% (its boundary stayed at least 90% the same).
- People, ACS 2020-2024
- 48,683
- 2020 Census count
- 47,289+9.4% since 2010 (43,236)
- Households
- 18,532
- Median age
- 40.6
Source: U.S. Census Bureau, ACS 2020-2024 5-year estimates (B01003, B01002, B11001); 2020 Census (DHC P1); 2010 Census (SF1 P1).
Who lives in 18104?
Of the 48,683 people the ACS estimates in 18104, 19.3% are under 18 and 20.5% are 65 or older. The largest group by race and Hispanic origin is White (not Hispanic) (66.1%), then Hispanic or Latino (17.1%).
- Under 1819.3%
- 18 to 6460.2%
- 65 and older20.5%
- White, not Hispanic66.1%
- Hispanic or Latino17.1%
- Asian, not Hispanic7.0%
- Black, not Hispanic6.7%
- Other or two or more3.1%
Source: U.S. Census Bureau, ACS 2020-2024 5-year estimates (B01001 age by sex, B03002 Hispanic or Latino origin by race); shares of the estimated population, small ZIP codes carry wide margins.
What do households in 18104 earn?
Median household income is $94,601 (ACS 2020-2024), the 12th highest of the 27 ranked ZIP codes in Lehigh County. It is not measurably different from 2015-2019 ($90,727 in 2024 dollars): the change is within the surveys' margins of error.
- Median household income
- $94,601
- Income per person
- $46,691
- Below the poverty line
- 8.3%
- Unemployed (of the labor force)
- 5.9%
- Adults 25+ with a bachelor's degree
- 46.1%
- Adjusted gross income per tax return, 2022
- $98,26724,340 returns; wages 64% of AGI (IRS)
Source: U.S. Census Bureau, ACS 2020-2024 and 2015-2019 5-year estimates (B19013, B19301, B17001, B23025, B15003; 2015-2019 dollars converted with the BLS CPI-U, 1.22699); IRS Statistics of Income, ZIP code data, tax year 2022 (adjusted gross income per return, filed under the address on the return).
What are homes worth in 18104?
FHFA's house price index for 18104, built from repeat sales and appraisals of the same homes, rose 97% from 2015 to 2025 and rose 63% from 2020 to 2025, and moved +6.5% in 2025.
- Median home value (owners' estimate)
- $336,400
- Median gross rent
- $1,637
- Homes owned by their occupants
- 71.0%
- Housing units
- 19,193
Source: U.S. Census Bureau, ACS 2020-2024 5-year estimates (B25077, B25064, B25003, B25001); FHFA House Price Index, annual five-digit ZIP, updated 2026-03-31.
What businesses are in 18104?
1,248 business establishments had a location in this ZIP code in 2023, 62 more than in 2018; the most are in health care and social assistance (ZIP Code Business Patterns).
- Health care and social assistance241
- Professional, scientific, and technical services154
- Retail trade133
- Accommodation and food services124
- Other services (except public administration)121
- Finance and insurance88
Source: U.S. Census Bureau, ZIP Code Business Patterns 2023 and 2018 (establishments with paid employees, by the business's ZIP code).
Which ZIP codes are next to 18104?
| ZIP | Town | People | Household income | Distance |
|---|---|---|---|---|
| 18106 | Allentown | 6,226 | $93k | 3.4 mi |
| 18069 | Orefield | 8,515 | $118k | 3.7 mi |
| 18102 | Allentown | 51,001 | $43k | 3.7 mi |
| 18052 | Whitehall | 29,451 | $76k | 3.9 mi |
| 18103 | Allentown | 48,746 | $73k | 4.2 mi |
| 18037 | Coplay | 7,472 | $84k | 4.9 mi |
| 18078 | Schnecksville | 7,857 | $121k | 5.6 mi |
| 18101 | Allentown | 6,120 | $45k | 4.1 mi (near) |
| 18046 | East Texas | 201 | – | 4.5 mi (near) |
| 18195 | Allentown | 0 | – | 4.5 mi (near) |
Source: PlainZIP from the Census 2020 ZCTA boundaries (shared edges) and internal points; figures ACS 2020-2024.