Residential delivery area · Pennsylvania
ZIP Code 18109: Allentown, PA
ZIP code 18109 uses the postal name Allentown, Pennsylvania and lies mostly in Lehigh County (95% of its land) with the rest in Northampton County (Census 2020 ZIP-county file). About 18,000 people live there (Census Bureau, ACS 2020-2024), the 4th most populous of Allentown's 7 residential ZIP codes. Median household income is $58,031 (Census Bureau, ACS 2020-2024). By Census place, 44% of its land lies in Allentown; 56% is outside any Census place.
- ACS2020-24
- Census2020
- FHFA2025
- ZBP2023
- IRS2022
- Town
- Allentown · 7 residential ZIPs
- County
- Lehigh County (95%); Northampton County (5%)
- Census places
- Allentown
- Neighborhoods
- Hanover Acres, Midway Manor, Ritterville GeoNames
- Metro area
- Allentown-Bethlehem-Easton, PA-NJ
- House district
- PA-7 119th Congress
- State
- Pennsylvania
- Time zone
- Eastern
- Land area
- 8.2 sq mi · 2,236 people per sq mi
- PO Box ZIPs
- 18105 also use the name Allentown
Where is ZIP code 18109?
18109 centers on 40.635°, -75.442° and covers 8.2 square miles of land plus 0.2 of water. It borders 8 ZIP codes: 18032, 18018, 18102, 18017, 18052, 18015, 18103, 18067.
The map draws ZIP code areas only. For the streets inside 18109, 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 18109 compare with the rest of Allentown?
| Measure | 18109 | In Allentown | In Lehigh County | In PA |
|---|---|---|---|---|
| People (ACS 2020-2024) | 18,446 | 4th of 7 | 10th of 35 | 223rd of 1,833 |
| Median household income | $58k | 4th of 6 | 25th of 27 | 851st of 1,015 |
| Median home value | $199k | 4th of 5 | 27th of 28 | 627th of 1,069 |
Its median household income is higher than in 26% of U.S. residential ZIP codes, and it is denser than 86% 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 18109?
The 2020 Census counted 18,915 people in 18109; the ACS, which samples households over 2020-2024, estimates 18,446. Between the 2010 and 2020 censuses its population grew 11.7% (its boundary stayed at least 90% the same).
- People, ACS 2020-2024
- 18,446
- 2020 Census count
- 18,915+11.7% since 2010 (16,932)
- Households
- 7,030
- Median age
- 36.6
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 18109?
Of the 18,446 people the ACS estimates in 18109, 22.9% are under 18 and 14.7% are 65 or older. The largest group by race and Hispanic origin is Hispanic or Latino (53.6%), then White (not Hispanic) (30.6%).
- Under 1822.9%
- 18 to 6462.3%
- 65 and older14.7%
- Hispanic or Latino53.6%
- White, not Hispanic30.6%
- Black, not Hispanic11.3%
- Other or two or more3.1%
- Asian, not Hispanic1.3%
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 18109 earn?
Median household income is $58,031 (ACS 2020-2024), the 25th highest of the 27 ranked ZIP codes in Lehigh County. It is not measurably different from 2015-2019 ($55,455 in 2024 dollars): the change is within the surveys' margins of error.
- Median household income
- $58,031
- Income per person
- $28,396
- Below the poverty line
- 18.1%
- Unemployed (of the labor force)
- 8.2%
- Adults 25+ with a bachelor's degree
- 16.0%
- Adjusted gross income per tax return, 2022
- $44,5999,670 returns; wages 83% 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 18109?
FHFA's house price index for 18109, built from repeat sales and appraisals of the same homes, rose 137% from 2015 to 2025 and rose 73% from 2020 to 2025, and moved +7.3% in 2025.
- Median home value (owners' estimate)
- $198,800
- Median gross rent
- $1,331
- Homes owned by their occupants
- 52.1%
- Housing units
- 7,519
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 18109?
802 business establishments had a location in this ZIP code in 2023, 84 more than in 2018; the most are in health care and social assistance (ZIP Code Business Patterns).
- Health care and social assistance103
- Retail trade92
- Other services (except public administration)84
- Accommodation and food services79
- Wholesale trade77
- Administrative and support and waste management and remediation services56
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 18109?
| ZIP | Town | People | Household income | Distance |
|---|---|---|---|---|
| 18032 | Catasauqua | 9,555 | $81k | 2.0 mi |
| 18018 | Bethlehem | 32,965 | $75k | 2.5 mi |
| 18102 | Allentown | 51,001 | $43k | 2.6 mi |
| 18017 | Bethlehem | 40,640 | $91k | 3.3 mi |
| 18052 | Whitehall | 29,451 | $76k | 3.6 mi |
| 18015 | Bethlehem | 34,852 | $61k | 5.2 mi |
| 18103 | Allentown | 48,746 | $73k | 5.1 mi |
| 18067 | Northampton | 19,590 | $94k | 6.0 mi |
| 18101 | Allentown | 6,120 | $45k | 2.7 mi (near) |
Source: PlainZIP from the Census 2020 ZCTA boundaries (shared edges) and internal points; figures ACS 2020-2024.