64,976 people (2024 Census estimate, −0.6% since 2020)
404 square miles of land · 161 people per square mile
“Highest” and “lowest” are just order, not grades: a high rank for poverty or hazard losses means more of it. Each figure's source is in its section below.
4 active community water systems list Marion County in the area they serve, reporting 48,290 people served in all (a system that crosses county lines counts its whole population).
| AQUA OHIO - MARION surface water · private · OH5100414 | 47,102 served |
| AQUA OHIO - LA RUE VILLAGE PWS groundwater · local government · OH5100312 | 800 served |
| PCM ARIA MARION LLC groundwater · private · OH5100212 | 230 served |
| PLEASANT ACRES MOBILE HOME COMMUNITY LLC groundwater · private · OH5100612 | 158 served |
Source: U.S. EPA Safe Drinking Water Information System (SDWIS), active community systems, . Look up any system's violations and test results with EPA's search using its ID.
About 152 people were held in Marion County's jail, in Vera's latest figure (2023), or 372 per 100,000 residents ages 15–64. In 2018 it was about 132.
Source: Vera Institute of Justice, Incarceration Trends (built from federal Bureau of Justice Statistics jail surveys). Counties without their own jail, or that share one, may show no figure.
6 school districts have their office in Marion County. School taxes are usually the largest part of a property tax bill.
Spent $70.7 million — $66 million to run schools, about $15,626 per student, plus $3.2 million on buildings and equipment. Money in: $12.2 million local (mostly property tax), $45.4 million state, $17.7 million federal. Long-term debt: $1 million.
Spent $25.7 million — $23.1 million to run schools, about $12,038 per student, plus $1.7 million on buildings and equipment. Money in: $14.5 million local (mostly property tax), $10.4 million state, $3 million federal. Long-term debt: $2.8 million.
Spent $21.8 million — $14.2 million to run schools, about $11,546 per student, plus $6.1 million on buildings and equipment. Money in: $11.2 million local (mostly property tax), $6.3 million state, $1.7 million federal. Long-term debt: $32.5 million.
Spent $15.6 million — $13.9 million to run schools, about $13,381 per student, plus $666,000 on buildings and equipment. Money in: $9.9 million local (mostly property tax), $8.1 million state, $1.6 million federal. Long-term debt: $14 million.
Spent $11.3 million — $9.7 million to run schools, about $15,397 per student, plus $1.4 million on buildings and equipment. Money in: $6.1 million local (mostly property tax), $4 million state, $2.4 million federal.
Spent $16.7 million — $13.6 million to run schools, about $26,428 per student, plus $1.3 million on buildings and equipment. Money in: $8.7 million local (mostly property tax), $7.7 million state, $1.1 million federal. Long-term debt: $557,000.
Source: U.S. Census Bureau, 2023 Annual Survey of School System Finances. Districts are listed by the county of their main office; some serve neighboring counties too.
Source: County Health Rankings & Roadmaps 2025 (University of Wisconsin Population Health Institute), which gathers federal data (CDC, Census, and others); measures cover different recent years. Blank lines aren't reported for small counties.
Overall risk: Relatively Low compared with other U.S. counties. FEMA estimates natural hazards cost Marion County about $19.7 million a year on average in buildings, crops and lives. Ability to bounce back (community resilience): Relatively High; social vulnerability: Relatively Moderate.
Source: FEMA National Risk Index (December 2025), expected annual loss. Ratings compare counties nationwide; they're estimates, not predictions.
230 bridges in Marion County: 139 in good condition, 82 fair, and 9 poor (3.9%). “Poor” means a main part — the deck, the beams, or the supports — is rated 4 or lower on the federal 0–9 scale. It doesn't mean unsafe to drive; unsafe bridges are closed.
| SR 231 over OVER US-23 · built 1968 | 1,476 vehicles a day |
| SR 203 over BATTLE RUN · built 1984 | 1,410 vehicles a day |
| SR 37 over SCIOTO RIVER · built 1950 | 699 vehicles a day |
| SR 746 over OLENTANGY RIVER · built 1955 | 605 vehicles a day |
| COUNTY ROAD 148 over BR OVER RIFFLE CREEK · built 1965 | 504 vehicles a day |
| TOWNSHIP ROAD 160 over MC KIBBEN DITCH · built 1965 | 324 vehicles a day |
Source: Federal Highway Administration, National Bridge Inventory (2025 submission). Includes state, county and city bridges.
Federal grants paid for $30.6 million of work in Marion County in fiscal 2025, about $468 per resident — to the county, cities, schools, hospitals, nonprofits and others.
Source: USAspending.gov, grants by place of performance, fiscal 2025 (Oct. 2024 to Sept. 2025). Search it by county to see each award.
From Grants.gov: posted grants listing county governments as eligible, soonest deadline first; research-only and overseas programs left out; list updated 2026-10-13, refreshed weekly. 62 are open in all. Cities, towns, school districts and nonprofits have their own lists there.
Registration deadlines, early voting and polling places for Ohio are on the federal site vote.gov, which links to the state's official election office.
The budget, property tax rates, audits, local officials and offices for Marion County come from the county's own records, which we haven't gathered — not gathered, never hidden. See what a full county site looks like, or ask to have Marion County built: brayden.ozark@gmail.com.
More of Ohio: the state government and every county in Ohio.
Nearby counties: Wyandot County (19 mi) · Morrow County (20 mi) · Crawford County (22 mi) · Union County (23 mi) · Delaware County (23 mi) · Hardin County (26 mi).