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U.S. ZIP Codes Database 2026

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ZIP Code Details for Oak

Detailed geographic and postal record lookup for the city of Oak.

Postal Information

ZIP Code 51439
Type Standard
Primary City Charter Oak
State IA
Acceptable Cities -
Unacceptable -
Time Zone America/Chicago
Area Codes 712
Latitude 42,06° N
Longitude -95,58° W

About U.S. ZIP Codes

U.S. ZIP Codes are 5-digit postal codes introduced in 1963 by the USPS to improve mail sorting efficiency. The first digit represents a broad region, the next two identify a sectional center facility, and the final two help pinpoint a local post office or delivery area.

Geographic Breakdown:

  • 1st Digit: Represents a group of states or a broad national region.
  • 2nd/3rd Digits: Represent a regional area or large city.
  • 4th/5th Digits: Identify specific post offices or delivery zones.

ZIP Codes support physical delivery, routing analytics, geocoding, tax calculations, and location-based research.

Geographic Map of Charter Oak, IA

Postal Information

ZIP Code 51560
Type Standard
Primary City Oakland
State IA
Acceptable Cities -
Unacceptable -
Time Zone America/Chicago
Area Codes 712
Latitude 41,3° N
Longitude -95,39° W

About U.S. ZIP Codes

U.S. ZIP Codes are 5-digit postal codes introduced in 1963 by the USPS to improve mail sorting efficiency. The first digit represents a broad region, the next two identify a sectional center facility, and the final two help pinpoint a local post office or delivery area.

Geographic Breakdown:

  • 1st Digit: Represents a group of states or a broad national region.
  • 2nd/3rd Digits: Represent a regional area or large city.
  • 4th/5th Digits: Identify specific post offices or delivery zones.

ZIP Codes support physical delivery, routing analytics, geocoding, tax calculations, and location-based research.

Geographic Map of Oakland, IA

Postal Information

ZIP Code 51566
Type Standard
Primary City Red Oak
State IA
Acceptable Cities -
Unacceptable -
Time Zone America/Chicago
Area Codes 712
Latitude 41,01° N
Longitude -95,22° W

About U.S. ZIP Codes

U.S. ZIP Codes are 5-digit postal codes introduced in 1963 by the USPS to improve mail sorting efficiency. The first digit represents a broad region, the next two identify a sectional center facility, and the final two help pinpoint a local post office or delivery area.

Geographic Breakdown:

  • 1st Digit: Represents a group of states or a broad national region.
  • 2nd/3rd Digits: Represent a regional area or large city.
  • 4th/5th Digits: Identify specific post offices or delivery zones.

ZIP Codes support physical delivery, routing analytics, geocoding, tax calculations, and location-based research.

Geographic Map of Red Oak, IA

Postal Information

ZIP Code 51591
Type Po Box
Primary City Red Oak
State IA
Acceptable Cities -
Unacceptable -
Time Zone America/Chicago
Area Codes 712
Latitude 41,01° N
Longitude -95,22° W

About U.S. ZIP Codes

U.S. ZIP Codes are 5-digit postal codes introduced in 1963 by the USPS to improve mail sorting efficiency. The first digit represents a broad region, the next two identify a sectional center facility, and the final two help pinpoint a local post office or delivery area.

Geographic Breakdown:

  • 1st Digit: Represents a group of states or a broad national region.
  • 2nd/3rd Digits: Represent a regional area or large city.
  • 4th/5th Digits: Identify specific post offices or delivery zones.

ZIP Codes support physical delivery, routing analytics, geocoding, tax calculations, and location-based research.

Geographic Map of Red Oak, IA

Postal Information

ZIP Code 52319
Type Po Box
Primary City Oakdale
State IA
Acceptable Cities -
Unacceptable -
Time Zone America/Chicago
Area Codes 319
Latitude 41,7° N
Longitude -91,6° W

About U.S. ZIP Codes

U.S. ZIP Codes are 5-digit postal codes introduced in 1963 by the USPS to improve mail sorting efficiency. The first digit represents a broad region, the next two identify a sectional center facility, and the final two help pinpoint a local post office or delivery area.

Geographic Breakdown:

  • 1st Digit: Represents a group of states or a broad national region.
  • 2nd/3rd Digits: Represent a regional area or large city.
  • 4th/5th Digits: Identify specific post offices or delivery zones.

ZIP Codes support physical delivery, routing analytics, geocoding, tax calculations, and location-based research.

Geographic Map of Oakdale, IA

Postal Information

ZIP Code 52646
Type Standard
Primary City Oakville
State IA
County Louisa County
Acceptable Cities -
Unacceptable Huron
Time Zone America/Chicago
Area Codes 309, 319
Latitude 41,09° N
Longitude -91,04° W

About U.S. ZIP Codes

U.S. ZIP Codes are 5-digit postal codes introduced in 1963 by the USPS to improve mail sorting efficiency. The first digit represents a broad region, the next two identify a sectional center facility, and the final two help pinpoint a local post office or delivery area.

Geographic Breakdown:

  • 1st Digit: Represents a group of states or a broad national region.
  • 2nd/3rd Digits: Represent a regional area or large city.
  • 4th/5th Digits: Identify specific post offices or delivery zones.

ZIP Codes support physical delivery, routing analytics, geocoding, tax calculations, and location-based research.

Geographic Map of Oakville, IA

Postal Information

ZIP Code 53065
Type Standard
Primary City Oakfield
State WI
Acceptable Cities -
Unacceptable -
Time Zone America/Chicago
Area Codes 920
Latitude 43,68° N
Longitude -88,54° W

About U.S. ZIP Codes

U.S. ZIP Codes are 5-digit postal codes introduced in 1963 by the USPS to improve mail sorting efficiency. The first digit represents a broad region, the next two identify a sectional center facility, and the final two help pinpoint a local post office or delivery area.

Geographic Breakdown:

  • 1st Digit: Represents a group of states or a broad national region.
  • 2nd/3rd Digits: Represent a regional area or large city.
  • 4th/5th Digits: Identify specific post offices or delivery zones.

ZIP Codes support physical delivery, routing analytics, geocoding, tax calculations, and location-based research.

Geographic Map of Oakfield, WI

Postal Information

ZIP Code 53154
Type Standard
Primary City Oak Creek
State WI
Acceptable Cities -
Unacceptable -
Time Zone America/Chicago
Area Codes 262, 414
Latitude 42,88° N
Longitude -87,89° W

About U.S. ZIP Codes

U.S. ZIP Codes are 5-digit postal codes introduced in 1963 by the USPS to improve mail sorting efficiency. The first digit represents a broad region, the next two identify a sectional center facility, and the final two help pinpoint a local post office or delivery area.

Geographic Breakdown:

  • 1st Digit: Represents a group of states or a broad national region.
  • 2nd/3rd Digits: Represent a regional area or large city.
  • 4th/5th Digits: Identify specific post offices or delivery zones.

ZIP Codes support physical delivery, routing analytics, geocoding, tax calculations, and location-based research.

Geographic Map of Oak Creek, WI

Postal Information

ZIP Code 54649
Type Po Box
Primary City Oakdale
State WI
County Monroe County
Acceptable Cities -
Unacceptable -
Time Zone America/Chicago
Area Codes 608
Latitude 43,96° N
Longitude -90,37° W

About U.S. ZIP Codes

U.S. ZIP Codes are 5-digit postal codes introduced in 1963 by the USPS to improve mail sorting efficiency. The first digit represents a broad region, the next two identify a sectional center facility, and the final two help pinpoint a local post office or delivery area.

Geographic Breakdown:

  • 1st Digit: Represents a group of states or a broad national region.
  • 2nd/3rd Digits: Represent a regional area or large city.
  • 4th/5th Digits: Identify specific post offices or delivery zones.

ZIP Codes support physical delivery, routing analytics, geocoding, tax calculations, and location-based research.

Geographic Map of Oakdale, WI

Postal Information

ZIP Code 56357
Type Standard
Primary City Oak Park
State MN
County Benton County
Acceptable Cities Foley, Ronneby
Unacceptable -
Time Zone America/Chicago
Area Codes 320, 763
Latitude 45,7° N
Longitude -93,8° W

About U.S. ZIP Codes

U.S. ZIP Codes are 5-digit postal codes introduced in 1963 by the USPS to improve mail sorting efficiency. The first digit represents a broad region, the next two identify a sectional center facility, and the final two help pinpoint a local post office or delivery area.

Geographic Breakdown:

  • 1st Digit: Represents a group of states or a broad national region.
  • 2nd/3rd Digits: Represent a regional area or large city.
  • 4th/5th Digits: Identify specific post offices or delivery zones.

ZIP Codes support physical delivery, routing analytics, geocoding, tax calculations, and location-based research.

Geographic Map of Oak Park, MN

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Postal context

About U.S. ZIP Codes

ZIP codes are a United States Postal Service system introduced in 1963 to make mail routing more accurate and efficient. The standard format uses five digits, while ZIP+4 adds four more digits for a more precise delivery segment.

ZIP codes cover the United States, its territories, military mail routes, and other USPS delivery points. This directory organizes that data for practical lookup by ZIP code, city, county, and state.