Oldest ZIP codes in Kootenai County, ID

These are the 10 ZIP codes in Kootenai County with the highest median age, out of 10 with at least 1,000 residents. 83810 (Cataldo, 64.0), 83833 (Harrison, 59.8) and 83876 (Worley, 50.1) lead the list. There is no single "best" ZIP code in Kootenai 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 Kootenai County

RankZIPMailing cityMedian ageResidentsHouseholdsResidential mailboxes
183810Cataldo64.0 ±8.91,412638510
283833Harrison59.8 ±5.51,365695—
383876Worley50.1 ±5.21,563622798
483814Coeur D Alene46.6 ±2.626,05911,96514,361
583835Hayden45.0 ±2.724,2389,110—
683869Spirit Lake44.9 ±6.35,5042,045—
783801Athol43.1 ±3.67,5532,622—
883858Rathdrum40.7 ±2.220,1377,2438,624
983815Coeur D Alene40.1 ±0.941,40516,657—
1083854Post Falls36.9 ±1.654,85120,05623,719

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; 10 of 11 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 23,030 households. Open any of them on the route map to see each carrier route's own figures before you choose.

Open 83810 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 Kootenai County has the highest median age?
83810 (Cataldo), at 64.0 (±8.9), among 10 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.