Area Code 557

Missouri

Area code 557 serves Missouri, primarily St. Louis, in the Central Time (CT) time zone. It is an overlay area code sharing territory with area code 314.

Overlay Area Code

This area code is part of an overlay region, meaning the same geographic area is served by multiple area codes. Overlay codes were introduced to meet growing demand for phone numbers without requiring existing customers to change their numbers.

This area code shares its geographic region with: area code 314 (St. Louis).

In service since: 12-Aug-2022

Learn more about overlay and split area codes →

Demographics & Economics

Total Population: 1,346,864
Population Density: 2,582 people/sq mi
above U.S. average (U.S.: 93 people/sq mi)
Median Household Income: $81,340
near U.S. median (U.S.: $75,144)
Poverty Rate: 13.8%
above U.S. average (U.S.: 11.5%)
Unemployment Rate: 4.5%
above U.S. average (U.S.: 3.6%)
Education Attainment: Bachelor's Degree+
44.1%
above U.S. average (U.S.: 33.7%)
High School or Lower
24.7%

Statistics are population-weighted aggregations from Census ACS 5-year estimates. Population figures are approximate — see Sources & Methodology for details on how area code populations are derived.

See how this area code compares to all US area codes in the Statistics dashboard.

Time Zone

Central Time (CT)

NANPA Relief Status

According to the latest NANPA analysis (July 2026), this area code is not currently listed as exhausting within the next 36 months. No relief planning is in progress for this NPA.

Source: NANPA NPA Relief Planning Reports · See all relief planning statuses

Current Time

Central Time (CT)

Prefix Utilization

Geographic Coverage

State

Major Cities

St. Louis
Florissant
Chesterfield
Oakville
Kirkwood
Mehlville
Maryland Heights
Hazelwood
Webster Groves
Old Jamestown
Affton
Creve Coeur
Ferguson
Spanish Lake
Concord
Clayton
Lemay
Overland
Jennings
St. Ann
Crestwood
Town and Country
Bridgeton
Bellefontaine Neighbors

and 65 more cities

Area Code 557 geographic coverage map (light mode)

History

Area code 557 serves as an overlay for the same territory as area code 314. It was introduced in 2022 to provide additional phone number capacity for the region. It shares its territory with area code area code 314.

Demographics

The estimated population served by area code 557 is approximately 1,346,864. The population density is 2,582 people per square mile, which is higher than the national average of 93. The median household income is $81,340, which is near the national median of $75,144. Approximately 44.1% of adults hold a bachelor's degree or higher, compared to the national rate of 33.7%. This rate is higher than the national average. The poverty rate stands at 13.8%, which is higher than the national rate of 11.5%.