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County ZIP codes · Michigan · FIPS 26071

Iron County, MI ZIP Codes

Iron County, Michigan has 9 ZIP codes (Census 2020 ZCTA-county file; GeoNames postal codes, October 2026): 8 residential and 1 for PO boxes or a single organization. 6 of the residential ones lie mainly in Iron County and 2 mainly in a neighboring county; 2 cross the county line. Median household income ranges from $49,471 in 49879 (Republic) to $63,605 in 49920 (Crystal Falls) (Census Bureau, ACS 2020-2024).

  • ACS2020-24
  • Census2020

Where are the ZIP codes of Iron County?

49879 · Republic: $50k49902 · Alpha: $39k49903 · Amasa: $42k49915 · Caspian: $35k49920 · Crystal Falls: $64k49927 · Gaastra: $48k49935 · Iron River: $57k49967 · Trout Creek: $44k49935499204996749879499034992749879 · Republic: $50k49902 · Alpha: $39k49903 · Amasa: $42k49915 · Caspian: $35k49920 · Crystal Falls: $64k49927 · Gaastra: $48k49935 · Iron River: $57k49967 · Trout Creek: $44k49935499204996749879499034992749879 · Republic: $50k49902 · Alpha: $39k49903 · Amasa: $42k49915 · Caspian: $35k49920 · Crystal Falls: $64k49927 · Gaastra: $48k49935 · Iron River: $57k49967 · Trout Creek: $44k4993549920499674987949903
The residential ZIP codes of Iron 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 8 postal town names: Iron River, Crystal Falls, Republic, Caspian, Trout Creek, Gaastra, Amasa, Alpha.

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

All 8 residential ZIP codes in Iron County

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

Residential ZIP codes mainly in Iron County, largest first; "In this county" is the share of the ZIP's land in the county
In this county
49935 Iron River 5,841 13 $57k $112k 100%
49920 Crystal Falls 4,380 11 $64k $130k 100%
49915 Caspian 570 473 $35k $79k 100%
49927 Gaastra 371 22 $48k $54k 100%
49903 Amasa 233 1 $42k $86k 100%
49902 Alpha 215 298 $39k $34k 100%

Partly in Iron County

Residential ZIP codes mainly in another county that reach at least 1% into Iron County, by their share here
In this county
49879 Republic 1,057 6 $50k $98k 37%
49967 Trout Creek 383 1 $44k $96k 19%

Download the 9 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?

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

Share of each ZIP code's land in Iron County and in the neighboring counties
ZIPIn IronElsewhere
4987937%Marquette County 63%
4996719%Houghton County 44%; Ontonagon County 37%

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

PO Box and single-organization ZIP codes

ZIP codes in Iron County without a residential area (GeoNames postal codes)
ZIPPostal name
49964Stambaugh

Source: GeoNames postal codes (CC BY 4.0).

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

The first three digits of a ZIP code name the sectional center, the mail processing plant that sorts it. Iron County's ZIP codes use 2 prefixes: 498 and 499.

Three-digit prefixes of Iron 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 Iron County's
PrefixSectional centerHereAll codes
498 Iron Mountain, MI (SCF 498) 1 68
499 Iron Mountain, MI (SCF 498) 8 47

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