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zipcodes.pro — METRO/20340-DUNCAN

Duncan, OK

ZIP codes
9
CBSA code
20340
Type
Micropolitan statistical area
States
OK
Population
43,551
Combined area
Lawton-Duncan, OK

Metro areas are defined by the Office of Management and Budget as whole counties, so every ZIP code in a member county is listed here.

Duncan in numbers

About 43,551 people live in the Duncan micropolitan area. The median household income is $61,620 a year (US: $80,734). The median owner-occupied home is valued at $145,300, and median gross rent is $895 a month.

Population43,551Duncan43,551
Median household income$61,620Duncan$61,620US $80,734
Median home value$145,300Duncan$145,300US $332,700
Median gross rent$895Duncan$895US $1,413

U.S. Census Bureau, American Community Survey 2020–2024 5-year estimates. Survey estimates carry margins of error, wider for small places. Sources and methods.

Its county

Counties in Duncan, OK
CountyZIP codesPopulationMedian income
Stephens County, OK 9 43,551 $61,620

ZIP codes in Duncan

ZIP codes in Duncan, OK
ZIP City Type Population Median income Median home
73055 Marlow , OK Standard 10,064 $65,991 $164,800
73425 Countyline , OK Standard 201 $35,637 —
73434 Foster , OK Standard 574 $63,214 $255,000
73442 Loco , OK Standard 275 $52,292 $133,900
73491 Velma , OK Standard 791 $83,750 $114,600
73529 Comanche , OK Standard 4,898 $70,143 $114,200
73533 Duncan , OK Standard 27,618 $59,906 $144,500
73534 Duncan , OK No street area — — —
73536 Duncan , OK No street area — — —

Cite this page

zipcodes.pro. “Duncan, OK.” Data release 2026-10-12. Retrieved 2026-10-20. https://zipcodes.pro/metro/20340-duncan

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