ZIP code 18631
Where is ZIP code 18631?
Mifflinville, Pennsylvania
Columbia County · PO Box only ZIP code
ZIP code 18631 belongs to Mifflinville, Pennsylvania in Columbia County. 18631 is a PO Box only ZIP code: it is used for post office boxes at the Mifflinville post office, not for street addresses. It is in the Eastern Time zone and uses area codes 272 and 570. About 1,100 people live in the 18631 area, where the median household income is $46,125. The closest ZIP codes are 18603 (Berwick, 4.1 mi northeast), 18635 (Nescopeck, 5.8 mi east) and 17859 (Orangeville, 6.1 mi northwest).
| ZIP code | 18631 |
|---|---|
| Type | PO Box only (no street delivery) |
| Status | Active |
| City | Mifflinville |
| State | Pennsylvania (PA) |
| County | Columbia County |
| Time zone | Eastern Time · now |
| Area codes | 272, 570 |
| Coordinates | 41.0323, -76.308 map |
| 3-digit prefix | 186 |
Population and income in 18631
| Population | 1,100 · lower than 62% of Pennsylvania ZIP codes |
|---|---|
| People per square mile | 774 · higher than 70% of Pennsylvania ZIP codes |
| Median age | 47 years · higher than 64% of Pennsylvania ZIP codes |
| Men / women | 49% / 51% |
| Median household income | $46,125 · lower than 94% of Pennsylvania ZIP codes |
| Income per person | $29,601 |
| Below the poverty line | 14% |
| Bachelor’s degree or higher | 30% of adults 25+ |
| Median home value | $214,100 · higher than 57% of Pennsylvania ZIP codes |
| Median rent | $959 a month |
| Housing units | 533 |
| Households | 517 (2.13 people on average) |
| Owners / renters | 78% / 22% |
| Land area | 1.42 sq mi (plus 0.17 sq mi of water) |
Source: U.S. Census Bureau, American Community Survey 5-year estimates (2020–2024) for ZIP Code Tabulation Area 18631. Census ZIP areas are close to, but not exactly the same as, USPS delivery areas.
ZIP codes near 18631
| ZIP code | City | Distance | Type |
|---|---|---|---|
| 18603 | Berwick, PA | 4.1 mi NE | Standard |
| 18635 | Nescopeck, PA | 5.8 mi E | Standard |
| 17859 | Orangeville, PA | 6.1 mi NW | Standard |
| 17815 | Bloomsburg, PA | 6.9 mi W | Standard |
| 18601 | Beach Haven, PA | 7.3 mi E | PO Box only |
| 18246 | Rock Glen, PA | 7.9 mi SE | PO Box only |
| 17878 | Stillwater, PA | 8.8 mi N | Standard |
| 18241 | Nuremberg, PA | 9.6 mi SE | Standard |
| 17985 | Zion Grove, PA | 10.1 mi SE | Standard |
| 18256 | Weston, PA | 10.4 mi SE | PO Box only |
| 17820 | Catawissa, PA | 10.5 mi SW | Standard |
| 18249 | Sugarloaf, PA | 11.3 mi E | Standard |
Straight-line distance between ZIP code center points. Find every ZIP code within 10 miles of 18631 or measure the distance to another ZIP code.
How to address mail to 18631
PO BOX 123
MIFFLINVILLE PA 18631
Put the city, the two-letter state code and the ZIP code on the last line. Adding the 4-digit ZIP+4 code (18631-XXXX) helps mail sort faster but isn’t required.
Questions
- What city is ZIP code 18631?
- 18631 is a Mifflinville, Pennsylvania ZIP code.
- What county is 18631 in?
- ZIP code 18631 is in Columbia County, Pennsylvania.
- What time zone is ZIP code 18631 in?
- 18631 is in the Eastern Time zone (America/New_York).
- What area code is 18631?
- Phone numbers in ZIP code 18631 use area codes 272 and 570.
- What is the population of ZIP code 18631?
- About 1,100 people live in ZIP code 18631, according to the Census Bureau’s American Community Survey (2020–2024).
- What is the median income in 18631?
- The median household income in 18631 is $46,125 a year, lower than 94% of Pennsylvania ZIP codes.
- Can I use 18631 for a street address?
- No. 18631 is only for PO Boxes. Street addresses in Mifflinville use another ZIP code.
- What ZIP codes are near 18631?
- The nearest ZIP codes to 18631 are 18603 (Berwick, 4.1 miles), 18635 (Nescopeck, 5.8 miles), 17859 (Orangeville, 6.1 miles) and 17815 (Bloomsburg, 6.9 miles).