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County ZIP codes · Iowa · FIPS 19071

Fremont County, IA ZIP Codes

Fremont County, Iowa has 11 ZIP codes (Census 2020 ZCTA-county file; GeoNames postal codes, October 2026), all residential. 9 of the residential ones lie mainly in Fremont County and 2 mainly in a neighboring county; 5 cross the county line. Median household income ranges from $62,143 in 51601 (Shenandoah) to $82,200 in 51652 (Sidney) (Census Bureau, ACS 2020-2024).

  • ACS2020-24
  • Census2020

Where are the ZIP codes of Fremont County?

51601 · Shenandoah: $62k51639 · Farragut: $85k51640 · Hamburg: $65k51645 · Imogene: $218k51647 · Northboro: $24k51648 · Percival: $60k51649 · Randolph: $58k51650 · Riverton: $49k51652 · Sidney: $82k51653 · Tabor: $71k51654 · Thurman: $90k516405160151652516545163951648516455164951653516505164751601 · Shenandoah: $62k51639 · Farragut: $85k51640 · Hamburg: $65k51645 · Imogene: $218k51647 · Northboro: $24k51648 · Percival: $60k51649 · Randolph: $58k51650 · Riverton: $49k51652 · Sidney: $82k51653 · Tabor: $71k51654 · Thurman: $90k516405160151652516545163951648516455164951653516505164751601 · Shenandoah: $62k51639 · Farragut: $85k51640 · Hamburg: $65k51645 · Imogene: $218k51647 · Northboro: $24k51648 · Percival: $60k51649 · Randolph: $58k51650 · Riverton: $49k51652 · Sidney: $82k51653 · Tabor: $71k51654 · Thurman: $90k5164051601516525165451639516485164551649516535165051647
The residential ZIP codes of Fremont County (whole outlines, including the parts in neighboring counties), shaded by median household income in national fifths (ACS 2020-2024). <$54.1k$98.1k+no figure

Source: U.S. Census Bureau, 2020 ZCTA cartographic boundaries; ACS 2020-2024 5-year estimates (B19013).

How different are its ZIP codes?

They carry 11 postal town names.

Source: U.S. Census Bureau, ACS 2020-2024 5-year estimates (B19013).

All 11 residential ZIP codes in Fremont County

9 ZIP codes lie mainly in Fremont County; 2 more reach into it from a neighboring county and follow the first table.

Residential ZIP codes mainly in Fremont County, largest first; "In this county" is the share of the ZIP's land in the county
In this county
51652 Sidney 1,569 21 $82k $135k 100%
51653 Tabor 1,446 41 $71k $230k 75%
51640 Hamburg 1,381 12 $65k $123k 82%
51639 Farragut 919 13 $85k $157k 100%
51645 Imogene 419 9 $218k – 57%
51649 Randolph 346 8 $58k $101k 100%
51654 Thurman 325 7 $90k $232k 100%
51648 Percival 257 4 $60k $164k 100%
51650 Riverton 197 6 $49k $54k 100%

Partly in Fremont County

Residential ZIP codes mainly in another county that reach at least 1% into Fremont County, by their share here
In this county
51601 Shenandoah 5,629 55 $62k $124k 37%
51647 Northboro 172 7 $24k – 25%

Download the 11 ZIP codes as CSV

Source: U.S. Census Bureau, ACS 2020-2024 5-year estimates; county shares by land area (Census 2020 ZCTA-county relationship file).

Which ZIP codes cross the county line?

5 ZIP codes of Fremont County extend into another county. A ZIP code follows mail routes, not county borders.

Share of each ZIP code's land in Fremont County and in the neighboring counties
ZIPIn FremontElsewhere
5160137%Page County 63%
5165375%Mills County 25%
5164082%Atchison County 18%
5164557%Mills County 30%; Montgomery County 7%; Page County 5%
5164725%Page County 75%

Source: U.S. Census Bureau, 2020 ZCTA-county relationship file (shares of land area).

Which first three digits do Fremont County's ZIP codes use?

The first three digits of a ZIP code name the sectional center, the mail processing plant that sorts it. Every ZIP code of Fremont County starts with 516.

Three-digit prefixes of Fremont County's ZIP codes, the sectional center for each (USPS labeling list L005, effective October 1, 2026) and how many of the prefix's codes are Fremont County's
PrefixSectional centerHereAll codes
516 Omaha, NE (SCF 680) 11 21

Source: U.S. Postal Service, labeling list L005 (3-digit ZIP Code prefix groups, SCF sortation), effective October 1, 2026.