Every ZIP code in the United States, with weather, radar, trivia and the numbers behind it. Five digits since 1963!

ZIP stands for Zone Improvement Plan. The codes went live on July 1, 1963.The lowest ZIP code is 00501 — the IRS in Holtsville, New York.The highest ZIP code is 99950, in Ketchikan, Alaska.Type 07734 into a calculator and turn it upside down: hELLO. It is Keansburg, New Jersey.12345 belongs to one company: General Electric in Schenectady, New York.The first digit is a region: 0 is New England and New Jersey, 9 is the West Coast, Alaska and Hawaii.Mr. ZIP, the cartoon mailman, was the mascot that sold the idea to America.ZIP+4 arrived in 1983 and can narrow a ZIP down to one side of one block.A ZIP code is a mail route, not a place: plenty of them cross county and even state lines.Play ZIP Hunt: guess the secret ZIP code of the day in six tries.
zipcodes.pro — STATE/SD/COUNTY/HAMLIN

Hamlin County, SD ZIP codes

Hamlin County, SD has 5 ZIP codes, in 5 towns: 57223, 57248, 57241, 57221 and 57242. 1 more crosses into it from a neighbouring county: 57234.

The county seat is Hayti.

ZIP codes
5
Partly in it
1 more
Towns
5
County seat
Hayti
County FIPS
46057
Population
6,373
Median household income
$87,101
Land area
507 sq mi

Hamlin County ZIP codes by town

Hayti (county seat)
57241

Each ZIP code is listed under the county most of its land lies in and the town the Postal Service names it for; a ZIP code's own page shows exactly how it is split.

ZIP codes partly in Hamlin County

This ZIP code lies mostly in a neighbouring county but covers a twentieth or more of Hamlin County.

Map of Hamlin County ZIP codes

5722157223572415724257248

The ZIP codes of Hamlin County, shaded. Outlines are Census ZIP Code Tabulation Areas (2020), which approximate the mail routes; PO-box and single-address codes have no area and are not drawn. Click any area to open its ZIP code.

Hamlin County in numbers

About 6,373 people live in Hamlin County, in 2,194 households, the 28th most populous of South Dakota's 66 counties. The median household income is $87,101 a year, 16% above the South Dakota median of $75,081 (US: $80,734). The median owner-occupied home is valued at $208,600 (19% below the South Dakota median), and median gross rent is $800 a month. The median age is 31.8; 24.5% of adults 25 and over hold a bachelor's degree or higher (31.9% across South Dakota); the average commute takes 22 minutes.

Population6,373Hamlin6,373
Households2,194Hamlin2,194
Median age31.8Hamlin31.8South Dakota38.0US 38.9
Median household income$87,101Hamlin$87,101South Dakota$75,081US $80,734
Median home value$208,600Hamlin$208,600South Dakota$257,400US $332,700
Median gross rent$800Hamlin$800South Dakota$946US $1,413
Bachelor's degree or higher24.5%Hamlin24.5%South Dakota31.9%US 35.7%
Mean commute22.2 minHamlin22.2 minSouth Dakota17.8 minUS 26.4 min
Population density13 / sq miHamlin13 / sq mi

U.S. Census Bureau, American Community Survey 2020–2024 5-year estimates. Survey estimates carry margins of error, wider for small places. Sources and methods.

Largest towns in Hamlin County

Largest towns in Hamlin County
TownZIP codesPopulation
Lake Norden 1 889
Castlewood 1 804
Bryant 1 727
Hayti 1 444
Hazel 1 199

Population of the census place of that name where there is one, otherwise of the ZIP codes the Postal Service addresses by it. A town's ZIP codes can reach past the county line.

Neighbouring counties

Counties that share a ZIP code with Hamlin County.

Not sure you are in Hamlin County? What county am I in? answers from your location, near a county line included.

Every ZIP code in Hamlin County, with figures

ZIP codes in Hamlin County
ZIP City Type Population Median income Median home
57221 Bryant , SD Standard 1,158 $73,988 $227,100
57223 Castlewood , SD Standard 1,429 $92,424 $236,600
57241 Hayti , SD Standard 936 $85,833 $123,000
57242 Hazel , SD Standard 320 $113,958 $177,100
57248 Lake Norden , SD Standard 1,295 $96,364 $293,200

Cite this page

zipcodes.pro. “Hamlin County ZIP codes.” Data release 2026-10-12. Retrieved 2026-10-20. https://zipcodes.pro/state/sd/county/hamlin

Underlying data is public domain or openly licensed — sources, vintages and licences.