108,140 people (2024 Census estimate, −2.2% since 2020)
673 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.
33 active community water systems list Mercer County in the area they serve, reporting 85,614 people served in all (a system that crosses county lines counts its whole population).
| AQUA PA SHENANGO VALLEY WTP surface water · private · PA6430054 | 48,000 served |
| AQUA PA GREENVILLE surface water · local government · PA6430037 | 8,600 served |
| GROVE CITY BORO WATER DEPT groundwater · local government · PA6430040 | 7,871 served |
| SHARPSVILLE BORO WATER CO buys surface water · local government · PA6430055 | 5,029 served |
| PINE TWP WATER DISTR SYSTEM buys groundwater · local government · PA6430061 | 3,082 served |
| REYNOLDS WATER COMPANY surface water · private · PA6430057 | 2,370 served |
| BUHL COMMUNITY WATER COMPANY groundwater · private · PA6430049 | 2,227 served |
| AQUA PA LAKE LATONKA WTP groundwater · private · PA6430059 | 1,600 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 231 people were held in Mercer County's jail, in Vera's latest figure (2023), or 348 per 100,000 residents ages 15–64. In 2018 it was about 277.
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.
12 school districts have their office in Mercer County. School taxes are usually the largest part of a property tax bill.
Spent $35.2 million — $33 million to run schools, about $16,239 per student, plus $644,000 on buildings and equipment. Money in: $21.2 million local (mostly property tax), $14 million state, $2.9 million federal. Long-term debt: $13.6 million.
Spent $42.2 million — $39.8 million to run schools, about $20,883 per student, plus $520,000 on buildings and equipment. Money in: $21.2 million local (mostly property tax), $19.9 million state, $4.2 million federal. Long-term debt: $29 million.
Spent $43.4 million — $39.1 million to run schools, about $20,851 per student, plus $1.1 million on buildings and equipment. Money in: $12.1 million local (mostly property tax), $30.5 million state, $6.3 million federal. Long-term debt: $40 million.
Spent $25.1 million — $22.2 million to run schools, about $17,365 per student, plus $713,000 on buildings and equipment. Money in: $8.1 million local (mostly property tax), $15.6 million state, $2.8 million federal. Long-term debt: $19.8 million.
Spent $21.2 million — $18.1 million to run schools, about $17,064 per student, plus $1.6 million on buildings and equipment. Money in: $8.4 million local (mostly property tax), $10.8 million state, $3 million federal. Long-term debt: $14.6 million.
Spent $18.6 million — $17.5 million to run schools, about $17,176 per student, plus $211,000 on buildings and equipment. Money in: $6.9 million local (mostly property tax), $11.8 million state, $1.9 million federal. Long-term debt: $11 million.
Spent $29.6 million — $20.5 million to run schools, about $21,493 per student, plus $8.1 million on buildings and equipment. Money in: $7.9 million local (mostly property tax), $13.9 million state, $3.2 million federal.
Spent $21.8 million — $19.4 million to run schools, about $22,883 per student, plus $1.4 million on buildings and equipment. Money in: $6.3 million local (mostly property tax), $11.9 million state, $3.3 million federal. Long-term debt: $8.1 million.
And 4 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 Mercer County about $34.1 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.
437 bridges in Mercer County: 179 in good condition, 193 fair, and 65 poor (14.9%). “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 58 MAIN STREET over OVER WOLF CREEK · built 1967 | 10,535 vehicles a day |
| SR 60 NB/SB BEAVER over OVER SR 18 S HERMITAGE · built 1966 | 7,590 vehicles a day |
| SR 18 NEW CASTLE R over OVER HOG BACK RUN · built 1941 | 7,414 vehicles a day |
| SR 60 DOCK ST over OVER OLD CANAL CREEK · built 1923 | 7,198 vehicles a day |
| Silver Street over Shenango River · built 1983 | 5,513 vehicles a day |
| SR 62 FRANKLIN RD. over OVER SPRING CREEK · built 1948 | 3,889 vehicles a day |
Source: Federal Highway Administration, National Bridge Inventory (2025 submission). Includes state, county and city bridges.
Federal grants paid for $156.8 million of work in Mercer County in fiscal 2025, about $1,417 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 Pennsylvania 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 Mercer 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 Mercer County built: brayden.ozark@gmail.com.
More of Pennsylvania: the state government and every county in Pennsylvania.
Nearby counties: Lawrence County (22 mi) · Venango County (26 mi) · Trumbull County, OH (27 mi) · Crawford County (28 mi) · Butler County (32 mi) · Mahoning County, OH (33 mi).