Oldest ZIP codes in Williamson County, IL

These are the 14 ZIP codes in Williamson County with the highest median age, out of 14 with at least 1,000 residents. 62951 (Johnston City, 50.1), 62933 (Energy, 48.6) and 62902 (Carbondale, 48.3) lead the list. There is no single "best" ZIP code in Williamson County; the right one depends on who you want to reach, so the same ZIP codes are ranked several ways below.

Oldest ZIP codes in Williamson County

RankZIPMailing cityMedian ageResidentsHouseholdsResidential mailboxes
162951Johnston City50.1 ±8.95,3422,440—
262933Energy48.6 ±14.51,101484—
362902Carbondale48.3 ±7.24,1351,8412,184
462922Creal Springs48.3 ±7.62,6081,0651,190
562917Carrier Mills48.3 ±8.02,303986—
662958Makanda46.4 ±4.32,1039421,024
762974Pittsburg43.6 ±7.91,536559529
862890Thompsonville42.5 ±5.12,3779891,075
962959Marion41.8 ±1.527,79311,953—
1062948Herrin40.2 ±2.612,7585,7295,766
1162924De Soto39.4 ±5.53,1681,3041,130
1262987Stonefort39.2 ±5.61,724586—
1362918Carterville38.0 ±3.010,6584,5214,606
1462901Carbondale25.2 ±0.622,9469,910—

How we ranked them

Ranked by median age of all residents, highest first (ACS 5-year estimates, 2020–2024). ZIP codes need at least 1,000 residents to be ranked; 14 of 18 qualify.

Which of these to mail, and why

Older ZIP codes respond to health care, hearing and vision, Medicare plans, home safety, estate planning and services that come to the door.

The top five ZIP codes on this list hold 6,816 households. Open any of them on the route map to see each carrier route's own figures before you choose.

Open 62951 on the EDDM route map

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Businesses that mail these ZIP codes

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Frequently asked questions

Which ZIP code in Williamson County has the highest median age?
62951 (Johnston City), at 50.1 (±8.9), among 14 ZIP codes with at least 1,000 residents.
How is this ranking calculated?
Ranked by median age of all residents, highest first (ACS 5-year estimates, 2020–2024).
Why are some ZIP codes missing?
ZIP codes with fewer than 1,000 residents are left out because their survey estimates swing too much to rank, and so are ZIP codes where the Census Bureau did not publish this figure.

This product uses the Census Bureau Data API but is not endorsed or certified by the Census Bureau.