🇺🇸 United States ZIP Code

STANDARD

61770

Saybrook

ZIP Code 61770 is a standard zip code serving Saybrook, Saybrook, Illinois (IL), in McLean County, United States. It has an estimated population of 1,108 with a median household income of $54,505. The area falls within the America/Chicago timezone.

Median Household Income vs. National Average

Location

Country: 🇺🇸 United States
State / Province: Illinois (IL)
County: McLean
City: Saybrook
Timezone: America/Chicago

Coordinates

Latitude: 40.432000
Longitude: -88.524700

Geographic Details

Land Area: 62.32 mi²
Water Area: 0.05 mi²
Population Density: 18.0 people per mi² (20th percentile)
Bounding Box: 40.529168°N, 40.368835°S, -88.459207°E, -88.612964°W

With 1,108 residents spread across 62.32 square miles, this area has a population density of 18.0 people per square mile.

Demographics

1,108

Population

25th percentile

$54,505

Median Income

65th percentile

$95,800

Median Home Value

30th percentile

62.32 mi²

Land Area

The median household income in 61770 is $54,505, and the median home value is $95,800.

Housing

503

Total Units

455

Occupied Units

90.5%

Occupancy Rate

Similar ZIP Codes in Illinois

ZIP codes with similar median household income in Illinois.

62440

Lerna

$59,231

61279

Reynolds

$52,917

61327

Hennepin

$62,054

62638

Franklin

$55,278

60130

Forest Park

$51,055

62208

Fairview Heights

$62,201

61739

Fairbury

$55,648

60647

Chicago

$51,675

Frequently Asked Questions

What information is available for each ZIP code?

Each ZIP code page shows city, state, county, geographic coordinates, timezone, population, median household income, median home value, housing units, land area, population density, commute time, educational attainment, area codes, and ZIP code type (Standard, PO Box, or Unique).

What are the different types of ZIP codes?

There are three types of ZIP codes: Standard (residential and commercial delivery areas), PO Box (assigned to post office box sections), and Unique (assigned to a single high-volume address like a government agency or large company). Standard ZIP codes are the most common.

How often is ZIP code data updated?

ZIP code assignments are updated quarterly by the USPS. Demographic data comes from the US Census Bureau's American Community Survey (ACS), which releases new 5-year estimates annually. ZipFYI updates its data to reflect the latest available information.

What is population density and why does it matter?

Population density measures the number of people per square mile in a ZIP code area. It helps identify urban vs. rural areas, affects real estate values, impacts service availability, and is used in market analysis. Dense urban ZIP codes may have 50,000+ people per square mile.

How are ZIP code boundaries determined?

ZIP code boundaries are determined by the USPS based on mail delivery routes, not political or geographic boundaries. They follow carrier routes and may cross city, county, or even state lines. Boundaries can change when the USPS reorganizes delivery operations.

What does median household income tell me about a ZIP code?

Median household income is the middle value when all household incomes in a ZIP code are sorted. Half of households earn more and half earn less. It is a better indicator of typical earnings than average income, which can be skewed by very high or very low outliers.