The map above shows Connecticut and South Dakota side by side at exactly the same scale, using equal-area projections, so their true relative sizes are preserved.
Connecticut vs South Dakota Geography
Land area: Connecticut has a land area of 4,843 square miles (12,542 km²), while South Dakota has 75,808 square miles (196,342 km²). South Dakota's land area is 15.7 times larger than Connecticut's.
Total area: Connecticut: 5,544 square miles (14,358 km²) vs South Dakota: 77,116 square miles (199,729 km²), including inland and coastal water. South Dakota's total area is 13.9 times larger than Connecticut's.
Length: Connecticut is 73 miles (118 km) long from north to south; South Dakota is 443 miles (712 km). South Dakota's north-south length is 6.1 times (507%) longer than Connecticut's.
Width: Connecticut spans 104 miles (167 km) east to west; South Dakota spans 371 miles (597 km). South Dakota's east-west width is 3.6 times (257%) wider than Connecticut's.
Highest point: Connecticut's highest point is Mount Frissell (south slope) at 2,376 feet (724 m); South Dakota's is Black Elk Peak at 7,198 feet (2,194 m). Black Elk Peak is 4,822 feet higher than Mount Frissell (south slope).
Lowest point: Connecticut's lowest point is Long Island Sound at 0 feet; South Dakota's is Big Stone Lake at 966 feet. Connecticut's lowest point is 966 feet lower.
Connecticut vs South Dakota Population and History
Population: Connecticut has a population of 3,675,069 (2024), while South Dakota has 924,669 (2024). Connecticut's population is 4.0 times (297%) larger than South Dakota's.
Population density: Connecticut: 758.9 people per square mile vs South Dakota: 12.2. Connecticut's population density is 62.2 times higher than South Dakota's.
Biggest city: Connecticut's biggest city is Bridgeport with 151,599 people; South Dakota's is Sioux Falls with 209,289. Sioux Falls' population is 1.4 times (38%) larger than Bridgeport's.
Largest metro area: Connecticut's largest metropolitan area is Hartford-West Hartford-East Hartford, CT metro area (1,169,048 people) vs South Dakota's Sioux Falls, SD-MN metro area (308,266). Hartford-West Hartford-East Hartford, CT metro area's population is 3.8 times (279%) larger than Sioux Falls, SD-MN metro area's.
History: Connecticut: Admitted to the Union on January 9, 1788, as the 5th state. South Dakota: Admitted to the Union on November 2, 1889, as the 40th state. In its current form, Connecticut is the older of the two by 101 years.
Connecticut vs South Dakota Economy
GDP: Connecticut's GDP is $356.8 billion (2024) vs South Dakota's $76.8 billion. Connecticut's economic output is 4.6 times (365%) larger than South Dakota's.
GDP per capita: Connecticut: $97,096 per person vs South Dakota: $83,052. Connecticut's GDP per capita is 1.2 times (17%) higher than South Dakota's.
Average income: Connecticut: $95,067 vs South Dakota: $75,699 average income per person (per capita personal income). Connecticut's average income is 1.3 times (26%) higher than South Dakota's.
Connecticut vs South Dakota Counties
Number of counties: Connecticut has 9 counties, while South Dakota has 66. South Dakota's county count is 7.3 times (633%) higher than Connecticut's.
Biggest county by area: Connecticut's largest county is Capitol Planning Region at 1,027 square miles; South Dakota's is Meade County at 3,471 square miles. Meade County's land area is 3.4 times (238%) larger than Capitol Planning Region's.
Smallest county by area: Connecticut: Greater Bridgeport Planning Region (140 sq mi) vs South Dakota: Clay County (412 sq mi). Clay County's land area is 2.9 times (194%) larger than Greater Bridgeport Planning Region's.
Most populous county: Connecticut: Capitol Planning Region (991,508 people) vs South Dakota: Minnehaha County (208,639 people). Capitol Planning Region's population is 4.8 times (375%) larger than Minnehaha County's.
Least populous county: Connecticut: Northeastern Connecticut Planning Region (97,701 people) vs South Dakota: Jones County (874 people). Northeastern Connecticut Planning Region's population is 111.8 times larger than Jones County's.
Richest county: Connecticut: Western Connecticut Planning Region ($165,513 per capita income) vs South Dakota: Union County ($146,712). Western Connecticut Planning Region's income is 1.1 times (13%) richer than Union County's.
Poorest county: Connecticut: Southeastern Connecticut Planning Region ($64,845 per capita income) vs South Dakota: Ziebach County ($32,778). Southeastern Connecticut Planning Region's income is 2.0 times (98%) richer than Ziebach County's.
Connecticut vs South Dakota Taxes
State income tax: Connecticut has a top income tax rate of 6.99%, while South Dakota has no state income tax. Connecticut's top rate is 6.99 percentage points higher.
Property tax: Connecticut: 1.66% effective rate vs South Dakota: 1.02% of home value per year. Connecticut's rate is 0.64 percentage points higher.
Sales tax: Connecticut: 6.35% combined state and average local rate vs South Dakota: 6.11%. Connecticut's combined rate is 0.24 percentage points higher.
Official Websites
Connecticut official website · South Dakota official website
More Size Comparisons
All Connecticut size comparisons · All South Dakota size comparisons
Area, elevation and boundary figures come from official national statistics and US Census Bureau and Natural Earth boundary data; US state population, economic, county and tax figures come from the US Census Bureau, the Bureau of Economic Analysis and the Tax Foundation. Figures are rounded and for general reference.