Saint Clair County

Saint Clair County, Michigan — key demographics

Population size

• Total: 160,383 (2020 Census)

Age

• Median age: 43.6 years (ACS 2019–2023)
• Under 18: 21.1% (ACS 2019–2023)
• 65 and over: 19.8% (ACS 2019–2023)

Gender

• Female: 50.6% (ACS 2019–2023)
• Male: 49.4% (ACS 2019–2023)

Racial/ethnic composition (ACS 2019–2023)

• White alone: 88.9%
• Black or African American alone: 4.4%
• American Indian and Alaska Native alone: 0.5%
• Asian alone: 0.7%
• Two or more races: 4.8%
• Hispanic or Latino (of any race): 4.0%
• White alone, not Hispanic or Latino: 86.0%

Households (ACS 2019–2023)

• Number of households: 63,200
• Persons per household: 2.47
• Family households: 66%
• Married-couple families: 49%
• Households with children under 18: 27%
• Owner-occupied housing rate: 78.6%
• Average family size: 3.00

Insights

• Stable-to-slightly declining population since 2020, with an older age profile (median age ~44).
• Predominantly White population with small but present Black and Hispanic communities.
• Household structure is largely owner-occupied and family-based, with roughly one-quarter having children.

Saint Clair County, MI (population ~160,000) has an estimated 125,000 regular email users.

Age distribution of email users (share of users):

• 13–17: 8%
• 18–34: 24%
• 35–54: 36%
• 55–64: 15%
• 65+: 17%

Gender split of email users:

• Female: 51%
• Male: 49%

Digital access and usage:

• About 85% of households subscribe to home broadband; smartphone‑only internet access is roughly 13%, sustaining high mobile email usage.
• Fixed broadband at ≥25/3 Mbps is available to over 95% of addresses; ≥100 Mbps service reaches roughly 90%, with adoption lagging in the more rural western and northern townships.
• Email penetration is near‑universal among adults under 55 (≈95%+), remains high for 55–64 (≈90%), and is substantial among 65+ (≈75–80%), reflecting the county’s older‑than‑average age profile.

Local density/connectivity facts:

• Population density is about 220 residents per square mile, with stronger cable/fiber coverage and higher adoption along the Port Huron and I‑94 corridors compared with outlying rural areas.
• Overall digital access has trended upward since 2020, driven by expanded cable/fiber builds and device affordability programs, steadily increasing email adoption across all age groups.

Summary of mobile phone usage in Saint Clair County, Michigan (most recent ACS- and industry-aligned estimates)

Headline user estimates

• Population and households: ≈160,000 residents; ≈64,000 households.
• Adult mobile users (any mobile phone): ≈117,000 (about 93% of adults).
• Adult smartphone users: ≈110,000 (about 88% of adults).
• Households with a smartphone: ≈89% (≈57,000 households).

Demographic and socioeconomic breakdown

• Age:
  • 18–34: smartphone adoption ≈96%.
  • 35–64: ≈92%.
  • 65+: ≈75% (several points lower than the Michigan average, reflecting the county’s older age profile).
• Income:
  • Households under $25k: cellular-only internet reliance ≈26%.
  • $25k–$74.9k: cellular-only ≈17%.
  • $75k+: cellular-only ≈8%.
• Education:
  • No college degree: notably higher likelihood of cellular-only service and prepaid plans than degree-holding peers.
• Geography within the county:
  • Port Huron/Fort Gratiot/Marysville corridor: higher 5G availability, lower cellular-only reliance (low-to-mid teens).
  • Rural townships inland: cellular-only shares commonly reach 20%+ and smartphone adoption among seniors is lower.

Connectivity and subscription profile

• Broadband of any type (household): ≈84%.
  • Wired broadband (cable/fiber/DSL): ≈70%.
  • Cellular data plan alone (cellular-only): ≈14%.
• No internet subscription: ≈16%.
• Device access:
  • Households with a computer (desktop/laptop/tablet): ≈86%.
  • Households without a computer or smartphone: ≈9%.

Digital infrastructure highlights

• Carrier presence: Verizon, AT&T, and T-Mobile provide countywide 4G LTE coverage across populated areas.
• 5G deployment:
  • Mid-band 5G (C-band/n41) is concentrated along I‑94/I‑69, Port Huron–Fort Gratiot, and other denser corridors, typically delivering 200–400 Mbps where available.
  • Rural sectors rely more on low‑band 5G/LTE, with common downlink speeds in the 5–50 Mbps range and occasional coverage gaps in sparsely populated interiors.
• Fixed wireless access (FWA):
  • T‑Mobile 5G Home and Verizon 5G Home are widely available across the main corridors and in/around Port Huron; LTE-based home internet options extend reach in rural tracts.
  • FWA adoption is rising as an alternative where cable/fiber is limited.
• Cross‑border context:
  • Proximity to Sarnia/Ontario (Blue Water Bridge, St. Clair River) drives above‑average Canada-roaming plan adoption and network selection behavior compared with the state overall.

How Saint Clair County differs from Michigan overall

• Higher cellular-only households: ≈14% vs a lower statewide share, indicating greater reliance on mobile data plans in place of wired broadband.
• Lower wired broadband take‑up and higher no‑internet share: ≈70% wired and ≈16% no subscription, both less favorable than Michigan averages, reflecting rural density and income mix.
• Older population effects: smartphone adoption among residents 65+ is several points below the state average, contributing to slightly lower overall adult smartphone penetration.
• Stronger role for fixed wireless: FWA is a more prominent substitute for cable/fiber than in metro‑heavy parts of Michigan.
• Cross‑border usage pattern: meaningful proportion of users incorporate Canada roaming—distinct from most Michigan counties not bordering Canada.

Implications

• Network planning: continued mid‑band 5G buildout beyond the I‑94/I‑69 corridor would directly address rural cellular‑only households and senior adoption barriers.
• Affordability and device programs: targeted subsidies and device-upgrade support in rural/low‑income tracts could reduce the ≈16% no‑internet share and raise senior smartphone adoption.
• FWA as bridge to fiber: fixed wireless will remain a critical stopgap where wired upgrades lag, with measurable impact on mobile data traffic patterns and plan selection.

St. Clair County, MI social media snapshot (2025)

Context and user base

• Population: ~160,000 residents; adults (18+) ≈125,000 (ACS 2023; using MI’s typical 18+ share).
• Most‑used platforms (share of U.S. adults who use; Pew Research Center 2024). Applying those rates to ~125k local adults gives the approximate local audience shown:
  • YouTube: 83% → ~104,000 adults
  • Facebook: 68% → ~85,000
  • Instagram: 47% → ~59,000
  • Pinterest: 35% → ~44,000
  • LinkedIn: 31% → ~39,000
  • TikTok: 33% → ~41,000
  • Snapchat: 30% → ~38,000
  • X (Twitter): 22% → ~28,000
  • Reddit: 22% → ~28,000

Age-group patterns (local behavior tracks Midwest suburban/rural norms)

• 18–24: Daily Snapchat/Instagram/TikTok; heavy group messaging; reacts to short, personality‑driven video and location filters.
• 25–34: Instagram Reels + TikTok for discovery; Facebook for events/Marketplace; YouTube for tutorials and product research.
• 35–54: Facebook is the hub (Groups, school/youth sports updates, local news) plus Marketplace; YouTube for how‑to and reviews; Instagram for local business content.
• 55+: Facebook first for community/news; YouTube for DIY, health, and travel; Instagram modest; TikTok growing but still lower.

Gender tendencies

• Women: Overrepresented on Facebook, Instagram, Pinterest; strong engagement with local schools, community groups, recipes, home projects, and Marketplace.
• Men: Overrepresented on YouTube, Reddit, X; high engagement with sports, automotive, outdoors, and local news.
• TikTok/Snapchat skew more by age than gender.

Behavioral trends specific to St. Clair County

• Community-first usage: Facebook Groups dominate for weather alerts, road closures, school updates, township news, and local events; rapid sharing during storms or incidents.
• Marketplace culture: Strong peer‑to‑peer selling (vehicles, tools, boats, household items); price‑sensitive buyers respond to limited‑time, hyperlocal offers.
• Visual-local affinity: Content featuring the Blue Water Bridge, St. Clair River/Lake Huron, and downtowns (Port Huron, Marine City, St. Clair) earns above‑average engagement; user‑generated photos/videos perform well.
• Seasonality: Summer spikes in boating/fishing, festivals, patio dining; late summer/back‑to‑school and pre‑winter home services see additional peaks.
• Small business use: Restaurants, boutiques, and home services lean on Facebook + Instagram; short vertical video (Reels/TikTok) boosts discovery; boosted posts with tight geo‑radius perform well around Port Huron, Marysville, St. Clair, and Fort Gratiot.
• Hiring: LinkedIn and Facebook Jobs effective for skilled trades, healthcare, and logistics; commuter corridors to Macomb/Detroit expand talent pools.
• News habits: Local outlets and scanner pages are high‑engagement on Facebook; breaking weather and traffic generate fast, broad reach.

Execution tips

• Timing: Weeknights 6–9 pm and weekend late mornings see reliable engagement; avoid weekday mid‑afternoon lulls.
• Creative: Lead with hyperlocal visuals, clear value, and map/tap‑to‑call; cross‑post short video to Reels and TikTok.
• Targeting: 5–15 mile radii around Port Huron/SC4 and major retail; interest clusters include boating, hockey, hunting/fishing, and home improvement.

Notes and sources

• Platform percentages: Pew Research Center, Social Media Use in 2024 (U.S. adults).
• Population base: U.S. Census Bureau, ACS 2023 1‑year. Local audience counts shown are modeled by applying national adoption rates to the county’s adult population.