Zip Code 45820 — Cairo, OH

45820 is a ZIP Code associated with Cairo, OH, located within Allen. 45820 ranks #10 out of 13 ZIP codes in Allen County by population (and #1002 out of 1,232 in OH). The area supports an estimated population of 581 residents across Data Pending housing units, with a population density of 809.8 people per square mile.
WorldPlaceData database updated: October 2026

📍 View location on OpenStreetMap (40.830740, -84.084730)

Data MetricLocal Statistic
Postal / Zip Code45820
Primary CityCairo
State / ProvinceOH
CountyAllen
Total Population581
Median Household IncomeData Pending
Total Housing UnitsData Pending
Population Density809.8 people/sq mi
TimezoneAmerica/New_York

How 45820 Compares

MetricZIP 45820Allen CountyOH State Average
Population581108,577 (Total)11,810,293 (Total)
Average ZIP IncomeData PendingN/AN/A
Population Density809.8 /sq mi----
County Pop Rank#10 of 13----

Nearby ZIP Codes

ZIP CodeCityDistancePopulationMedian Income
Zip 45807Lima4.6 mi11,774N/A
Zip 45801Lima4.6 mi21,739N/A
Zip 45893Vaughnsville4.7 mi160N/A
Zip 45830Columbus Grove5.2 mi5,199N/A
Zip 45809Gomer5.3 mi45N/A

Data Sources & Methodology: Geographic coordinates and ZIP Code assignments are derived from underlying geographic and postal datasets. Note that ZIP Codes are USPS postal delivery areas, while Census ZCTAs are statistical approximation areas. Read full methodology →