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U.S. ZIP Codes Database 2026

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ZIP Code Details for Rockford

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

Postal Information

ZIP Code 61101
Type Standard
Primary City Rockford
State IL
County Winnebago County
Acceptable Cities -
Unacceptable -
Time Zone America/Chicago
Area Codes 779, 815
Latitude 42,35° N
Longitude -89,15° 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 Rockford, IL

Postal Information

ZIP Code 61102
Type Standard
Primary City Rockford
State IL
County Winnebago County
Acceptable Cities -
Unacceptable -
Time Zone America/Chicago
Area Codes 779, 815
Latitude 42,23° N
Longitude -89,16° 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 Rockford, IL

Postal Information

ZIP Code 61103
Type Standard
Primary City Rockford
State IL
County Winnebago County
Acceptable Cities Machesney Park, Machesney Pk
Unacceptable -
Time Zone America/Chicago
Area Codes 779, 815
Latitude 42,34° N
Longitude -89,09° 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 Rockford, IL

Postal Information

ZIP Code 61104
Type Standard
Primary City Rockford
State IL
County Winnebago County
Acceptable Cities -
Unacceptable -
Time Zone America/Chicago
Area Codes 779, 815
Latitude 42,25° N
Longitude -89,08° 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 Rockford, IL

Postal Information

ZIP Code 61105
Type Po Box
Primary City Rockford
State IL
County Winnebago County
Acceptable Cities -
Unacceptable -
Time Zone America/Chicago
Area Codes 815
Latitude 42,27° N
Longitude -89,06° 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 Rockford, IL

Postal Information

ZIP Code 61106
Type Po Box
Primary City Rockford
State IL
County Winnebago County
Acceptable Cities -
Unacceptable -
Time Zone America/Chicago
Area Codes 815
Latitude 42,27° N
Longitude -89,06° 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 Rockford, IL

Postal Information

ZIP Code 61107
Type Standard
Primary City Rockford
State IL
County Winnebago County
Acceptable Cities -
Unacceptable -
Time Zone America/Chicago
Area Codes 779, 815
Latitude 42,27° N
Longitude -89,06° 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 Rockford, IL

Postal Information

ZIP Code 61108
Type Standard
Primary City Rockford
State IL
County Winnebago County
Acceptable Cities -
Unacceptable -
Time Zone America/Chicago
Area Codes 779, 815
Latitude 42,26° N
Longitude -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 Rockford, IL

Postal Information

ZIP Code 61109
Type Standard
Primary City Rockford
State IL
County Winnebago County
Acceptable Cities -
Unacceptable Morristown, New Milford
Time Zone America/Chicago
Area Codes 779, 815
Latitude 42,19° N
Longitude -89,06° 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 Rockford, IL

Postal Information

ZIP Code 61110
Type Po Box
Primary City Rockford
State IL
County Winnebago County
Acceptable Cities -
Unacceptable -
Time Zone America/Chicago
Area Codes 815
Latitude 42,27° N
Longitude -89,06° 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 Rockford, IL

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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.