Every ZIP code in the United States, with weather, radar, trivia and the numbers behind it. Five digits since 1963!

ZIP stands for Zone Improvement Plan. The codes went live on July 1, 1963.The lowest ZIP code is 00501 — the IRS in Holtsville, New York.The highest ZIP code is 99950, in Ketchikan, Alaska.Type 07734 into a calculator and turn it upside down: hELLO. It is Keansburg, New Jersey.12345 belongs to one company: General Electric in Schenectady, New York.The first digit is a region: 0 is New England and New Jersey, 9 is the West Coast, Alaska and Hawaii.Mr. ZIP, the cartoon mailman, was the mascot that sold the idea to America.ZIP+4 arrived in 1983 and can narrow a ZIP down to one side of one block.A ZIP code is a mail route, not a place: plenty of them cross county and even state lines.Play ZIP Hunt: guess the secret ZIP code of the day in six tries.
zipcodes.pro — CITY/IA/PLAINFIELD

Plainfield ZIP code, Iowa

The ZIP code for Plainfield, IA is 50666, and its area code is 319.

USPS city name
1 ZIP code
Population
314
Area code
319
State
Iowa

Plainfield in numbers

About 314 people live in Plainfield, in 132 households. The median household income is $80,000 a year, 7% above the Iowa median of $75,059 (US: $80,734). The median owner-occupied home is valued at $128,100 (38% below the Iowa median), and median gross rent is $684 a month. The median age is 43.7; 15.0% of adults 25 and over hold a bachelor's degree or higher (31.4% across Iowa); the average commute takes 22 minutes.

Population314Plainfield314
Households132Plainfield132
Median age43.7Plainfield43.7Iowa38.6US 38.9
Median household income$80,000Plainfield$80,000Iowa$75,059US $80,734
Median home value$128,100Plainfield$128,100Iowa$208,000US $332,700
Median gross rent$684Plainfield$684Iowa$972US $1,413
Bachelor's degree or higher15.0%Plainfield15.0%Iowa31.4%US 35.7%
Mean commute22.1 minPlainfield22.1 minIowa19.8 minUS 26.4 min
Population density935 / sq miPlainfield935 / sq mi

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

ZIP codes addressed as Plainfield

ZIP codes with the USPS city name Plainfield
ZIP City Type Population Median income Median home
50666 Plainfield , IA Standard 753 $79,867 $203,700

Map of Plainfield ZIP codes

50666

The ZIP codes of Plainfield, IA, shaded. Outlines are Census ZIP Code Tabulation Areas (2020), which approximate the mail routes; PO-box and single-address codes have no area and are not drawn. Click any area to open its ZIP code.

Towns near Plainfield

The nearest larger towns are Nashua (1,622 people, 7.3 mi), Clarksville (1,237 people, 8.1 mi) and Waverly (10,494 people, 9.1 mi).

Towns near Plainfield
TownPopulationDistance
Waverly 10,494 9.1 mi
Charles City 7,232 16.8 mi
New Hampton 3,453 18.4 mi
Cedar Falls 40,888 22.9 mi
Waterloo 67,008 26.1 mi
Hudson 2,699 28.6 mi
Evansdale 4,518 29.5 mi

More nearby: every ZIP code in Bremer County · Iowa ZIP codes

Cite this page

zipcodes.pro. “Plainfield, IA ZIP codes.” Data release 2026-10-12. Retrieved 2026-10-20. https://zipcodes.pro/city/ia/plainfield

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