Sully County GIS Maps

Sully County Maps

The maps below show a few of the county map styles included in our downloads. County packages include map exports in JPEG, PNG, SVG, PDF and GeoTIFF formats plus more than 20 GIS layers for mapping, research and analysis. Available layers include zip codes, area codes, subdivisions, school districts, political boundaries, roads, water features, points of interest and more.

County packages also include historical county demographics, business intelligence, analytical dashboards, AI-ready prompts, markdown files and related reference data. Everything is organized to save hours of manual work collecting current data, cleaning it and joining it together. That makes it easier to move faster on analytics, due diligence, business planning and location research. Paid packages are built for commercial use, but some package contents include source-specific attribution or notice guidance. Review Licensing & Data Source Notices.

Sully County Population

Sully County had 1,446 residents in 2020. That was 5.3% higher than in 2010. Sully County had 110 fewer people in 2020 than it did in 2000, which points to a long-term population decline. The county is fairly spread out, with about 1 people per square mile. Two of the county's most populated postal areas are Onida and Agar.

Population Trend in Sully County SD

Sully County Population per 2000, 2010 and 2020 census counts with a baseline 2030 projection.

Sully County Zip Codes

Sully County has 2 zip codes. Two of the county's most populated zip codes are Onida (57564) and Agar (57520). Onida is the largest zip by population, with about 963 residents or 67% of the county total. Together, the three largest zips account for about 76% of all county residents based on 2020 population estimates.

Most Populated Zip Codes in Sully County SD

Sully County Zip Code populations and trends per most recent census data.

Sully County Demographics

Sully County has a median age of 51.4, which makes the county a little older than South Dakota overall. About 19.4% of residents are under 18, while 23.8% are 65 or older. That gives the county a fairly even mix of younger families and older adults. The largest age group is 45 to 64 at about 26.5% of the population, which points to a solid working-age base. About 20.9% of adults have a bachelor's degree or higher, above the statewide figure of 31.1%. The county is mostly White by population, though Hispanic, Asian, Black and multiracial residents are also part of the local mix.

Key Demographics for Sully County SD

Sully County School Districts

Sully County is served by 2 public school districts with 445 students enrolled in 2024. Several larger districts account for a substantial share of students across the county map area. Those three districts account for about 100% of public school enrollment in the map area. Total enrollment has stayed fairly steady in recent years, but it is slightly lower than it was in 2017.

Largest School Districts by Enrollment in Sully County SD

Sully County school district enrollment and trends per most recent NCES reporting data.

Sully County Housing & Real Estate

Sully County has a median home value of $198,700 and a median gross rent of $913. About 76% of occupied homes in the county are owner-occupied, so the local housing market leans heavily toward ownership. Home values run below the South Dakota median, while rents come in above the state average. In March 2026, the median listing price was $704,950 and homes spent about 113 days on the market.

Businesses in Sully County, SD

Sully County has 99 business listings across 59 categories. The largest categories in Sully County business listings are Lodge (9, 9.1%), Churches & Religious Organizations (5, 5.1%), and Agricultural Service (4, 4.0%). The full Sully County business listings dataset includes names, categories, addresses and contact details where available. Sully County packages also include U.S. Census County Business Patterns data with establishment counts, employment and payroll by industry sector.

Top Business Categories in Sully County, SD

Sully County Business Listings

Sully County business listings sourced from Overture Maps. Includes locations with a high level of confidence.

Sully County Basemaps

Sully County map and data packages include a set of useful basemaps to help you get started quickly. These include a custom light grey canvas, USGS topo, imagery and other reference layers that make it easier to build clear, meaningful county maps using the included GIS layers, your own data or both. Pre-rendered map tiles for the light grey basemap are included so you can use them offline or host them on your own CDN.

Preview a Live Package Demo

See exactly what is included in a county data package. Inspect how files are organized, the interactive data explorer and how maps and analytics are laid out. The demo loads a real sample package from South Dakota — explore the full structure before you buy.