Tripp County area

Tripp County, South Dakota covers 1,617.4 square miles: 1,612.3 square miles of land and 5.151 square miles of water. Its county seat is Winner. An estimated 5,708 people lived there in 2025.

Official Census measurements · GEOID 461232026 Gazetteer · retrieved September 27, 2026
Land area1,612.3 mi²
Water area5.151 mi²
Population (2025)5,708
People per mi²3.5

County outline

Generalized outline of Tripp County, South Dakota
2025 Census cartographic boundary, fitted to this frame. County maps are not at a common scale. The 2026 area measurements below come from the separate Gazetteer release. Map source and limitations.

Where Tripp County is located

Tripp County highlighted on a map of all U.S. county equivalents. About the maps

Area breakdown

Land accounts for 99.7% of Tripp County’s measured area and water for 0.3%. Its combined area converts to 4,189.2 square kilometers or approximately 1,035,162 acres.

Green: land · blue: water

MeasurementSquare milesSquare kilometersAcres
Land1,612.2894,175.8091,031,865
Water5.15113.3413,296.6
Total1,617.444,189.151,035,161.6

How Tripp County compares

By original Census land area, Tripp County ranks #15 of 66 in South Dakota and #377 of 3,222 nationally. National rankings include the 50 states, District of Columbia, and Puerto Rico.

Its land area is 1.773 times the South Dakota county-equivalent median of 909.3 square miles. It accounts for 2.1% of the combined county land area in the state.

See the complete South Dakota ranking · What counts as a county equivalent?

Population and density of Tripp County

The Census Bureau estimates that 5,708 people lived in Tripp County on July 1, 2025. That ranks #2,835 of 3,222 county equivalents nationally and #31 of 66 in South Dakota. Since the April 1, 2020 estimates base of 5,628, the population has grown by 80 (+1.4%), compared with +5.5% for South Dakota as a whole.

With 1,612.3 square miles of land, that is 3.5 people per square mile (1.4 per km²), placing Tripp County #2,943 nationally for density and #46 in South Dakota. The median county equivalent has 47 people per square mile; the South Dakota median is 5.7. Put another way, there are about 181 acres of land per resident.

Estimated population, 2020–2025 · line scaled to this county’s own range
July 1202020212022202320242025
Estimate5,6065,5765,5745,6975,7385,708
Change—−30−2+123+41−30

U.S. Census Bureau, Vintage 2025 population estimates. Estimates are revised each year and are not decennial census counts. Density divides the whole population by the whole county’s land area, so it describes an average, not how settlement is distributed within the county. Population sources and methods.

Cities and towns in Tripp County

3 incorporated places lie at least partly in Tripp County. Together they are home to 3,361 people (58.9%); the other 2,347 (41.1%) live outside any incorporated place, in unincorporated communities and rural areas.

The largest is Winner city, with 2,969 residents in the county.

Incorporated placePopulation 2025Since 2020Land mi²
Winner cityCounty seat2,969+1.9%2.292
Colome city337+2.1%0.282
New Witten town55+1.9%0.277

Population: U.S. Census Bureau Vintage 2025 subcounty estimates, counting only the part of each place inside Tripp County. Land: 2026 Census Gazetteer, for the whole place even where it extends into other counties. How communities are listed.

Metropolitan area

Tripp County is not part of any metropolitan or micropolitan statistical area in the Office of Management and Budget’s July 2023 delineation; 1,306 other county equivalents are also outside one. These areas are built around an urban core of at least 10,000 people plus the counties tied to it by commuting, so counties outside them are generally rural.

ZIP codes

8 ZIP Code Tabulation Areas have land in Tripp County; 6 of them have most of their land inside the county, and the others mainly cover neighboring areas.

5752857529575335753457541575445758057584

ZIP Code Tabulation Areas are the Census Bureau’s approximations of USPS ZIP Code service areas, from the 2020 Census relationship files. Lighter codes have less than half of their land in this county. Post-office-box and single-address ZIP Codes have no tabulation area.

Counties bordering Tripp County

Tripp County shares a land border with 5 county equivalents, including 1 in Nebraska. It has more land than 4 of them. The largest neighbor is Lyman County (1,642.3 mi²) and the smallest is Keya Paha County (772.9 mi²). Together with its neighbors, Tripp County forms a block of 7,738.3 mi² of land, of which it holds 20.8%.

Map of Tripp County and the 5 county equivalents that border it Lyman County, South Dakota: 1,642.3 mi² landGregory County, South Dakota: 1,015 mi² landKeya Paha County, Nebraska: 772.9 mi² landTodd County, South Dakota: 1,388.6 mi² landMellette County, South Dakota: 1,307.3 mi² land
Tripp County (dark) and its bordering county equivalents. Select a neighbor to open its profile. Drawn from the 2025 Census cartographic boundaries in an equal-area projection. How borders are determined.
Bordering county equivalentLand mi²Size vs. TrippCompare
Lyman County1,642.3about the sameCompare
Todd County1,388.61.2× smallerCompare
Mellette County1,307.31.2× smallerCompare
Gregory County1,0151.6× smallerCompare
Keya Paha CountyNebraska772.92.1× smallerCompare

How big is Tripp County compared with U.S. states?

Tripp County has more land than 1 of the 50 states. It is about 1.6 times the land area of Rhode Island (1,033.9 mi²), while Delaware, the next larger state, has 1.2 times as much land (1,948.6 mi²). South Dakota’s county land could hold about 47 areas the size of Tripp County.

Land area: Tripp County and the closest-sized states
Rhode Island1,033.9 mi²
Tripp County1,612.3 mi²
Delaware1,948.6 mi²

Another way to picture it: the same land area would fill a square about 40.2 miles (64.6 km) on each side. Real county shapes are rarely square, so this is a scale reference rather than a width or driving distance.

State figures are the sums of each state’s county-equivalent land measurements in the same Census release, so states and counties are compared on the same basis. Published state totals can differ slightly because of rounding. Compare all states · Counties bigger than entire states.

What stands out about Tripp County?

Tripp County has more land than 2,845 of the other 3,221 county equivalents in the dataset.

Land area compared with the typical county equivalent
Tripp County1,612.3 mi²
South Dakota median909.3 mi²
National median604.5 mi²

A median is the middle county-equivalent measurement, not the average of the largest and smallest. All three bars use the same linear scale. Very small areas may appear as a thin sliver; the labels retain their values.

Does including water change its rank?

Using land plus water places Tripp County at #416 nationally by total area, 39 places farther from the top than its land rank. Other county equivalents gain more area when their water measurements are included.

Its water share is 0.3%, compared with a national county-equivalent median of 1.2% — 0.9 percentage points lower. This describes the statistical geography’s land/water mix, not flood exposure or developable land.

Closest positions in the national land ranking

These entries sit immediately beside Tripp County in the national ranking. They can be in different states and are not necessarily geographic neighbors.

Land rankCounty equivalentLand mi²Comparison
#376Jackson County, Colorado1,613.7Compare
#377Tripp County, South Dakota1,612.3This county
#378Coos County, Oregon1,596.1Compare

Calculated from the same Census release as the area table. Total-area order uses original ALAND + AWATER; water shares and chart labels use published square miles. Calculation details.

Representative coordinates

The Census internal point is 43.349729, -99.876219. It represents a location inside the geography; it is not necessarily the centroid or the address of a courthouse.

Source and precision

U.S. Census Bureau, 2026 Gazetteer Files, Counties. Original ALAND: 4,175,808,479 m²; AWATER: 13,340,586 m². Rankings use ALAND; exact ties use ascending GEOID. Tables preserve Census-published square miles to three decimals, with conversions based on those values.

Download the official county source ZIP ↗ · Methodology

Common questions

How big is Tripp County?

Tripp County, South Dakota has 1,612.3 square miles (4,175.8 km²) of land and 5.151 square miles of water, for a total area of 1,617.4 square miles. It ranks #377 of 3,222 U.S. county equivalents by land area.

Is Tripp County the largest county in South Dakota?

No. Tripp County ranks #15 of 66 in South Dakota by land area. The largest is Meade County, with 3,470.9 square miles of land.

What counties border Tripp County?

Tripp County shares a land border with Lyman County, Gregory County, Keya Paha County, Nebraska, Todd County, and Mellette County.

What is the population of Tripp County?

The Census Bureau estimates Tripp County had 5,708 residents on July 1, 2025, ranking #2,835 of 3,222 county equivalents. That is 3.5 people per square mile of land.

What is the county seat of Tripp County?

The county seat of Tripp County is Winner.

What cities and towns are in Tripp County?

Tripp County has 3 incorporated places. The most populous are Winner city, Colome city, and New Witten town; 2,347 residents live outside any incorporated place.

Is Tripp County part of a metropolitan area?

No. Tripp County is outside every metropolitan and micropolitan statistical area in the July 2023 OMB delineation.

How many ZIP codes are in Tripp County?

8 ZIP Code Tabulation Areas have land in Tripp County, and 6 of them have most of their land inside the county. Census ZIP Code Tabulation Areas approximate USPS ZIP Code areas.

How does Tripp County compare with U.S. states?

It has more land than 1 of the 50 states, including Rhode Island (1,033.9 square miles of land).

How many acres of land are in Tripp County?

The land measurement converts to approximately 1,031,865 acres. Including water, total area is approximately 1,035,162 acres. One square mile equals 640 acres.

Why might another source show a different area?

Check whether it reports land or total area, its Census vintage, and its rounding. Our guide explains how to reconcile county area figures.

Can this establish a property boundary?

No. Statistical measurements and generalized maps do not establish property lines. Consult the relevant local surveying or land-records authority.

Cite this county

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