Pennington County

Pennington County, South Dakota — key demographics (latest Census/ACS estimates)

Population

• Total population: ~114,000 (2023 ACS 1-year), up from 109,222 in 2020 (+4–5% growth)

Age

• Median age: ~37 years
• Under 18: ~24%
• 18–64: ~59%
• 65 and over: ~17%

Sex

• Male: ~50.5%
• Female: ~49.5%

Race and ethnicity (mutually exclusive; Hispanic is of any race)

• Non-Hispanic White: ~76%
• American Indian and Alaska Native (non-Hispanic): ~11%
• Hispanic/Latino (any race): ~7%
• Black or African American (non-Hispanic): ~2%
• Asian (non-Hispanic): ~1–2%
• Native Hawaiian/Other Pacific Islander (non-Hispanic): ~0.2%
• Two or more races (non-Hispanic): ~3%

Households and families

• Total households: ~46,000
• Average household size: ~2.4
• Family households: ~60% of households; average family size ~3.0
• Households with children under 18: ~29%
• Living alone: ~29% of households (about one-third of these are 65+)
• Housing tenure: ~63% owner-occupied, ~37% renter-occupied

Insights

• Population growth since 2020 outpaces many rural Great Plains counties, driven by the Rapid City area and Ellsworth AFB.
• The county is relatively young compared with the U.S. median, with a sizable working-age share.
• A large American Indian population (about one in nine residents) and a growing Hispanic population shape the county’s diversity.
• Household structure skews toward smaller households, with a solid owner-occupancy majority and a sizable renter segment.

Sources: U.S. Census Bureau, 2023 American Community Survey (1-year) and 2019–2023 ACS (5-year); 2020 Decennial Census.

Pennington County, SD email usage snapshot (2025)

• Population and access: ~116,000 residents; ~88,000 adults (18+); ~47,000 households. About 88–90% of households have a broadband subscription; an estimated 15–20% are smartphone‑only internet users. 5G coverage is widespread in Rapid City; fiber is expanding in and around urban corridors, while rural areas rely more on DSL and fixed wireless.

• Estimated email users: ~90,000 residents (≈92% of adults plus most teens), equal to roughly 78% of the total population.

• Age distribution using email:

  • 13–17: ~80%
  • 18–29: ~97%
  • 30–49: ~96%
  • 50–64: ~92%
  • 65+: ~85%

• Gender split among adult email users: approximately even; women ~51%, men ~49%.

• Trends: Mobile‑first email access is rising with strong 5G in Rapid City and growing smartphone‑only households. Older‑adult adoption continues to climb due to telehealth, banking, and government services. Rural gaps persist where terrain limits wired speeds.

• Local density/connectivity: Population density ≈41 people/sq mi; about two‑thirds of residents live in Rapid City, where speeds and provider competition are highest. Many outer townships are <10 people/sq mi and show lower subscription and email usage.

Mobile phone usage snapshot — Pennington County, South Dakota (2025)

Headline takeaways

• Population baseline: ~116,000 residents (2023 estimate). Adults (18+): ~89,000.
• Estimated mobile phone users: ~98,000 residents (≈85% of the population).
• Estimated smartphone users: ~91,000 residents (≈79% of the population); ~81,000 adult smartphone users (≈91% of adults).
• Coverage: Virtually universal 4G/LTE in populated areas; robust mid‑band 5G across Rapid City/Box Elder and the I‑90/US‑16 corridors; patchier 5G in the western/northwestern Black Hills.

User estimates by age (rounded)

• Ages 12–17: ~8,900 residents; mobile phone users ~8,600 (≈97%); smartphone users ~8,500 (≈95%).
• Ages 18–34: ~26,700 residents; mobile phone users ~26,400 (≈99%); smartphone users ~25,900 (≈97%).
• Ages 35–64: ~41,800 residents; mobile phone users ~40,500 (≈97%); smartphone users ~38,400 (≈92%).
• Ages 65+: ~20,900 residents; mobile phone users ~18,400 (≈88%); smartphone users ~16,700 (≈80%).
• Children under 12: ~17,800 residents; mobile phone users ~4,400 (≈25%); smartphone users ~1,800 (≈10%).

Demographic and socioeconomic patterns

• Urban vs rural: Approximately four in five residents live in the Rapid City–Box Elder urban area. Urban residents show smartphone adoption a few points higher than rural counterparts and are more likely to have 5G devices, reflecting better mid‑band 5G coverage and denser site grids in the metro.
• Income: Smartphone carry rates are high across brackets but still stratify: roughly low-income 83–88%, middle-income ~90%, higher-income ~95%. Mobile-only internet (cellular without fixed broadband) is more common among lower-income renters in Rapid City, especially after the end of new ACP enrollments in 2024.
• Age: The 65+ cohort remains the main gap—about 1 in 5 older adults still use either a basic handset or no mobile at all. Younger cohorts are near‑universal smartphone carriers.
• Native American residents (≈10–12% of the county): Higher likelihood of prepaid plans and mobile‑only internet relative to White households, driven by affordability and housing mobility; adoption levels generally track state urban Native communities more than rural reservation areas.

Digital infrastructure and performance

• Radio access
  • 4G/LTE: Near‑universal coverage across populated areas of the county; reliable along I‑90, US‑16, and SD‑44 corridors.
  • 5G: T‑Mobile mid‑band (n41 “UC”) broadly available in Rapid City/Box Elder and key travel corridors; Verizon and AT&T C‑band/5G+ in core urban zones and along I‑90. 5G reaches most residents but does not cover the full land area of the Black Hills.
• Typical performance (mobile data)
  • Urban core (Rapid City/Box Elder): Mid‑band 5G median downloads commonly 150–300 Mbps; LTE fallback 20–80 Mbps.
  • Suburban/edge: 5G low/mid‑band 50–150 Mbps; LTE 10–40 Mbps.
  • Mountainous/heavily forested areas (e.g., canyons west/south of Rapid City, parts of SD‑44/SD‑40/SD‑385): LTE often available; speeds can drop into single‑digit Mbps; 5G intermittent.
• Capacity dynamics
  • Seasonal surge May–September from tourism (Black Hills/Mount Rushmore) and regional events increases traffic notably; operators add portable capacity and extra spectrum carriers near venues and along I‑90.
  • Public safety: AT&T FirstNet sites densified around Rapid City, highways, and key recreation areas; agencies increasingly use cellular as secondary data backhaul alongside the state’s LMR network.

How Pennington County differs from South Dakota overall

• Higher smartphone penetration: Pennington’s adult smartphone rate (~91%) sits a few points above the statewide average, reflecting its more urban profile, younger median, and presence of a military base and service economy.
• More extensive mid‑band 5G: The county has materially better mid‑band 5G availability and capacity than much of rural South Dakota, yielding faster median speeds and lower congestion in the metro.
• Lower mobile‑only internet share than rural counties: Because Rapid City has robust cable and expanding fiber builds (e.g., recent overbuilds), the share of households relying only on cellular data is lower than in many rural SD counties, even as mobile‑only is still significant among lower‑income renters.
• Smaller coverage gaps but sharper terrain limits: Compared with the state as a whole, Pennington’s gaps are less about distance and more about topography—canyon/valley shadowing in the Black Hills, rather than broad, flat‑plains dead zones common elsewhere in SD.
• Greater seasonal volatility in demand: The county experiences stronger summer peaks due to tourism, which is less pronounced in many eastern SD counties.

Notes on method and sources

• Population and age structure: U.S. Census Bureau 2023 estimates.
• Adoption rates: Applied Pew Research Center 2023–2024 U.S. smartphone/cellphone ownership by age and rural/urban status to the county’s demographics to produce user counts.
• Coverage and performance: Aggregated from FCC mobile coverage data (2023–2024) and carrier public network disclosures, aligned with known buildouts in Rapid City/Box Elder and along I‑90/US‑16.
• Figures are county‑level estimates designed to be decision‑ready and to highlight meaningful differences from statewide patterns.

Social media usage in Pennington County, SD (2025 snapshot)

How many users

• Total residents: ≈116,000 (2023 estimate). Residents 13+: ≈96,000.
• Estimated active social media users: ≈70,000–73,000 (about 61–63% of the total population; 73–76% of residents 13+).

Age mix of users (share of all social media users)

• 13–17: ~8%
• 18–29: ~22%
• 30–49: ~35%
• 50–64: ~22%
• 65+: ~13%

Gender breakdown of users

• Female: ~52%
• Male: ~48%

Most-used platforms (estimated share of residents 13+ who use each at least monthly)

• YouTube: 83%
• Facebook: 68%
• Instagram: 44%
• TikTok: 32%
• Pinterest: 33% (heavily female)
• Snapchat: 27% (heaviest among teens/young adults)
• LinkedIn: 26% (professional/education clusters in Rapid City area)
• X (Twitter): 20%
• Reddit: 19%
• Nextdoor: 7% (limited neighborhood penetration)

Behavioral trends

• Community-first usage: Facebook Groups and Marketplace are central for local news, weather alerts, school updates, garage sales, lost-and-found, and events across Rapid City/Black Hills.
• Video-heavy consumption: YouTube dominates for local news clips, how-to, outdoor/hunting/ATV content, and regional tourism; short-form video (Reels/TikTok) is the preferred format under age 35.
• Youth patterns: Snapchat and TikTok drive daily messaging and short video among high-school and college-aged users, with peak activity after school/evenings.
• Visual outdoors ethos: Instagram and TikTok engagement centers on trails, parks, wildlife, scenic drives, and local dining; user-generated photo/video outperforms stock imagery.
• Timing: Consistent peaks around 7–9 a.m., 12–1 p.m., and 7–10 p.m. local time; weekend mid-days are strong for event and family content; weather events meaningfully spike Facebook and YouTube activity.
• Shopping and discovery: Facebook Marketplace is a key channel for used goods and local services; giveaways, limited-time offers, and event tie-ins outperform generic brand ads.
• Messaging: Facebook Messenger is ubiquitous among adults; Snapchat DMs among younger users; community pages and DMs often convert better than link-out ads.
• Trust signals: Content from recognizable local organizations, schools, first responders, veteran/military–adjacent groups, and small businesses sees higher engagement and share rates.

Notes on method

• Figures are model-based estimates applying recent U.S. platform-adoption rates (Pew Research Center, 2024) to Pennington County’s age structure (U.S. Census Bureau 2023 estimates), with minor adjustments for local urban–rural mix. Percentages reflect residents 13+ unless noted.