256,059 people (2024 Census estimate, +5.3% since 2020)
401 square miles of land · 638 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.
16 active community water systems list Warren County in the area they serve, reporting 213,579 people served in all (a system that crosses county lines counts its whole population).
| WARREN COUNTY groundwater · local government · OH8301512 | 99,000 served |
| WESTERN WATER COMPANY buys surface water · private · OH8300512 | 39,508 served |
| LEBANON CITY buys surface water · local government · OH8304112 | 20,700 served |
| SPRINGBORO PWS groundwater · private · OH8301412 | 19,263 served |
| FRANKLIN PUBLIC WATER SYSTEM groundwater · private · OH8300412 | 11,690 served |
| SOUTH LEBANON CITY PWS buys surface water · local government · OH8301312 | 7,792 served |
| WAYNESVILLE VILLAGE PWS groundwater · local government · OH8302012 | 4,100 served |
| LEBANON CORRECTIONAL INSTITUTION groundwater · state · OH8301012 | 3,410 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 274 people were held in Warren County's jail, in Vera's latest figure (2023), or 168 per 100,000 residents ages 15–64. In 2018 it was about 283.
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.
9 school districts have their office in Warren County. School taxes are usually the largest part of a property tax bill.
Spent $151.4 million — $140.8 million to run schools, about $13,834 per student, plus $7.3 million on buildings and equipment. Money in: $109.6 million local (mostly property tax), $45.8 million state, $7.9 million federal. Long-term debt: $6 million.
Spent $71.2 million — $63.1 million to run schools, about $10,364 per student, plus $5.8 million on buildings and equipment. Money in: $51.3 million local (mostly property tax), $22 million state, $4.7 million federal. Long-term debt: $40.2 million.
Spent $73.8 million — $63.6 million to run schools, about $11,754 per student, plus $3 million on buildings and equipment. Money in: $52 million local (mostly property tax), $19 million state, $4.6 million federal. Long-term debt: $99.2 million.
Spent $77.5 million — $66.8 million to run schools, about $12,521 per student, plus $3.9 million on buildings and equipment. Money in: $46.9 million local (mostly property tax), $25.7 million state, $6.2 million federal. Long-term debt: $72.7 million.
Spent $70.4 million — $66.7 million to run schools, about $13,429 per student, plus $1.7 million on buildings and equipment. Money in: $52.9 million local (mostly property tax), $16 million state, $5.3 million federal. Long-term debt: $33.9 million.
Spent $79.6 million — $42.4 million to run schools, about $16,597 per student, plus $31.8 million on buildings and equipment. Money in: $25.5 million local (mostly property tax), $16.4 million state, $3.9 million federal. Long-term debt: $66.7 million.
Spent $26.7 million — $20.2 million to run schools, about $12,496 per student, plus $4.6 million on buildings and equipment. Money in: $15 million local (mostly property tax), $6.3 million state, $863,000 federal. Long-term debt: $23.8 million.
Spent $25.4 million — $23 million to run schools, about $14,530 per student, plus $1.2 million on buildings and equipment. Money in: $13 million local (mostly property tax), $10.4 million state, $1.6 million federal. Long-term debt: $19.5 million.
And 1 more.
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 Warren County about $61.8 million a year on average in buildings, crops and lives. Ability to bounce back (community resilience): Very High; social vulnerability: Very Low.
Source: FEMA National Risk Index (December 2025), expected annual loss. Ratings compare counties nationwide; they're estimates, not predictions.
338 bridges in Warren County: 205 in good condition, 115 fair, and 18 poor (5.3%). “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.
| I75 RAMP over DICKS CREEK · built 1960 | 91,260 vehicles a day |
| US 22 over BEAR RUN · built 1938 | 16,452 vehicles a day |
| UNION ROAD over SHAKER CREEK · built 1969 | 5,762 vehicles a day |
| FRANKLIN-TRENTON over DRY RUN · built 1981 | 4,573 vehicles a day |
| TOWNSHIP LINE ROAD over NEWMANS RUN · built 1920 | 2,477 vehicles a day |
| MORROW-COZADDALE over BIG FOOT RUN · built 1977 | 2,437 vehicles a day |
Source: Federal Highway Administration, National Bridge Inventory (2025 submission). Includes state, county and city bridges.
Federal grants paid for $31.7 million of work in Warren County in fiscal 2025, about $131 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 Warren 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 Warren County built: brayden.ozark@gmail.com.
More of Ohio: the state government and every county in Ohio.
Nearby counties: Clinton County (19 mi) · Butler County (21 mi) · Greene County (23 mi) · Montgomery County (24 mi) · Hamilton County (25 mi) · Clermont County (26 mi).