55,880 people (2024 Census estimate, +3.4% since 2020)
829 square miles of land · 67 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 Johnson County in the area they serve, reporting 66,549 people served in all (a system that crosses county lines counts its whole population).
| MO AMERICAN WARRENSBURG groundwater · private · MO1010833 | 18,500 served |
| JOHNSON COUNTY PWSD 2 groundwater · local government · MO1024310 | 12,490 served |
| WHITEMAN AIR BASE groundwater · federal · MO1079501 | 10,106 served |
| LAF JO SALINE COUNTY CONS PWSD 2 buys surface water · local government · MO1024326 | 7,180 served |
| JOHNSON COUNTY PWSD 3 groundwater · local government · MO1024311 | 5,317 served |
| JOHNSON COUNTY PWSD 1 groundwater · local government · MO1024309 | 4,240 served |
| KNOB NOSTER PWS groundwater · local government · MO1010432 | 2,863 served |
| HOLDEN PWS surface water · local government · MO1010371 | 2,683 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 141 people were held in Johnson County's jail, in Vera's latest figure (2021), or 379 per 100,000 residents ages 15–64. In 2016 it was about 186.
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.
7 school districts have their office in Johnson County. School taxes are usually the largest part of a property tax bill.
Spent $45.5 million — $41.5 million to run schools, about $12,274 per student, plus $1.1 million on buildings and equipment. Money in: $23 million local (mostly property tax), $19.9 million state, $5.4 million federal. Long-term debt: $47.9 million.
Spent $23.9 million — $21.5 million to run schools, about $11,273 per student, plus $2.3 million on buildings and equipment. Money in: $4.5 million local (mostly property tax), $10.6 million state, $10.1 million federal.
Spent $20.5 million — $14.6 million to run schools, about $11,894 per student, plus $4.9 million on buildings and equipment. Money in: $7.7 million local (mostly property tax), $7.1 million state, $2.3 million federal. Long-term debt: $16.3 million.
Spent $7.6 million — $6.3 million to run schools, about $11,802 per student, plus $588,000 on buildings and equipment. Money in: $3.4 million local (mostly property tax), $3.4 million state, $2 million federal. Long-term debt: $4.9 million.
Spent $4 million — $3.5 million to run schools, about $10,476 per student, plus $87,000 on buildings and equipment. Money in: $1.7 million local (mostly property tax), $2.4 million state, $656,000 federal. Long-term debt: $1.4 million.
Spent $3.6 million — $3.5 million to run schools, about $13,685 per student, plus $15,000 on buildings and equipment. Money in: $1.9 million local (mostly property tax), $1.4 million state, $251,000 federal. Long-term debt: $1.6 million.
Spent $2.2 million — $2.1 million to run schools, about $13,082 per student, plus $60,000 on buildings and equipment. Money in: $964,000 local (mostly property tax), $1.2 million state, $223,000 federal.
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 Johnson County about $24.3 million a year on average in buildings, crops and lives. Ability to bounce back (community resilience): Relatively Moderate; social vulnerability: Very Low.
Source: FEMA National Risk Index (December 2025), expected annual loss. Ratings compare counties nationwide; they're estimates, not predictions.
475 bridges in Johnson County: 166 in good condition, 276 fair, and 33 poor (6.9%). “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.
| US 50 E over UP RR · built 1968 | 8,279 vehicles a day |
| US 50 W over UP RR · built 1956 | 6,420 vehicles a day |
| WASHINGTON AVE over BR OF LONG BR CR · built 1998 | 1,000 vehicles a day |
| RT M S over SNAIL CR · built 1947 | 552 vehicles a day |
| RT V E over COLBURN CR · built 1951 | 551 vehicles a day |
| RT TT E over HORNSBY BR · built 1955 | 345 vehicles a day |
Source: Federal Highway Administration, National Bridge Inventory (2025 submission). Includes state, county and city bridges.
Federal grants paid for $33.5 million of work in Johnson County in fiscal 2025, about $621 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 Missouri 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 Johnson 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 Johnson County built: brayden.ozark@gmail.com.
More of Missouri: the state government and every county in Missouri.
Nearby counties: Lafayette County (23 mi) · Henry County (25 mi) · Pettis County (28 mi) · Cass County (30 mi) · Jackson County (34 mi) · Ray County (40 mi).