Explore stored Illinois operator, county, formation, permit, and well records. The contributing tables refresh independently; check the source dates and coverage before comparing figures.
Source refresh dates: some dates unavailable Source: Illinois Department of Natural Resources, Office of Oil & Gas · separate source dates below
Researching an operator or well activity is one part of understanding a mineral or royalty interest.
The tables combine independently refreshed records. These dates describe the stored source records, rather than when this page was opened. An unavailable date does not establish a zero count.
Operator rankings:
Permit records: through
DUC records: Refresh date unavailable
Spud records: Refresh date unavailable
Producing-well records: Refresh date unavailable
County activity:
Formation summaries:
State-regulator records are compiled through a commercial well-data aggregator. The snapshot reflects the records held in these tables and is not a complete statewide census.
The 10 largest operators of record in Illinois, by total well count. See the full top-100 leaderboard →
| # | Operator | Wells | Permits 24mo | DUCs | Top Formation | Top County |
|---|---|---|---|---|---|---|
| 1 | The Ohio Oil | 10,782 | 0 | 0 | Illinois Basin | Crawford |
| 2 | Marathon Oil Company | 4,529 | 0 | 0 | Illinois Basin | Lawrence |
| 3 | The Texas Company | 4,094 | 0 | 0 | Illinois Basin | Marion |
| 4 | Pure Oil Company | 3,223 | 0 | 0 | Illinois Basin | Richland |
| 5 | Texaco | 2,427 | 0 | 0 | Illinois Basin | Marion |
| 6 | Ohio Oil Company | 2,181 | 0 | 0 | Illinois Basin | Crawford |
| 7 | The Pure Oil Company | 1,935 | 0 | 0 | Illinois Basin | Wayne |
| 8 | The Carter Oil | 1,812 | 0 | 0 | Illinois Basin | Fayette |
| 9 | Forest Oil | 1,678 | 0 | 0 | Illinois Basin | Cumberland |
| 10 | Magnolia Petroleum Company | 1,605 | 0 | 0 | Illinois Basin | Marion |
The 10 most-active oil and gas counties in Illinois. See the full county rankings →
| County | Total Wells | Permits 24mo | Spuds 90d | DUCs | Top Operator | Top Formation |
|---|---|---|---|---|---|---|
| Lake | 31,424 | 0 | 0 | 0 | Il State Geological Survey | Michigan Basin |
| Crawford | 28,731 | 43 | 0 | 0 | The Ohio Oil | Illinois Basin |
| Will | 25,446 | 0 | 0 | 0 | Il State Geological Survey | Wisconsin Arch |
| Mc Henry | 24,295 | 0 | 0 | 0 | Il State Geological Survey | Wisconsin Arch |
| White | 18,588 | 148 | 0 | 11 | Superior Oil Company | Illinois Basin |
| Lawrence | 18,007 | 6 | 0 | 0 | The Ohio Oil | Illinois Basin |
| Cook | 17,440 | 0 | 0 | 0 | Illinois State Geological Survey | Michigan Basin |
| Wayne | 15,406 | 2 | 0 | 0 | The Pure Oil Company | Illinois Basin |
| Peoria | 14,725 | 0 | 0 | 0 | Central Il Light Company | Illinois Basin |
| Kane | 13,722 | 0 | 0 | 0 | Il State Geological Survey | Wisconsin Arch |
The 10 most-active formations and plays in Illinois. See all active Illinois formations →
| Formation | Wells | Active Operators | Permits 24mo |
|---|---|---|---|
| Illinois Basin | 199,349 | 13,021 | 502 |
| Wisconsin Arch | 3,692 | 336 | 15 |
| Michigan Basin | 621 | 98 | 0 |
| New Albany | 477 | 264 | 0 |
| Lake Michigan | 61 | 5 | 0 |
| Permit Date | Well | API | County | Formation | Operator |
|---|---|---|---|---|---|
| 2026-07-30 | Centralia 3-Hor | 121212856800 |
Marion | Illinois Basin | Ameren Illinois Company |
| 2026-07-29 | Centralia 2-Hor | 121212856700 |
Marion | Illinois Basin | Ameren Illinois Company |
| 2026-07-28 | Obc 25-3 | 121992422000 |
Williamson | Illinois Basin | Keyrock Energy |
| 2026-07-27 | Howell 7-B Hor | 121212857000 |
Marion | Illinois Basin | Schwartz Oil Properties |
| 2026-07-27 | Freeburg 19-Hor | 121633175100 |
St Clair | Illinois Basin | Ameren Illinois Company |
| 2026-07-27 | Illinois Minerals 19-1 | 120552533600 |
Franklin | Illinois Basin | Stewart Producers |
| 2026-07-27 | Howell 6-C Hor | 121212856900 |
Marion | Illinois Basin | Schwartz Oil Properties |
| 2026-07-23 | Boarman 6 | 121672843500 |
Sangamon | Illinois Basin | Keyrock Energy |
| 2026-07-23 | Boarman 7 | 121672843400 |
Sangamon | Illinois Basin | Keyrock Energy |
| 2026-07-23 | Harrelson 1-A | 120552533800 |
Franklin | Illinois Basin | Gesells Pump Sales Service |
Explore the Illinois owner guides above, or use the inquiry form to share the location of your interests.
Get Your Free Written OfferSource: Illinois Department of Natural Resources, Office of Oil & Gas well-header and production filings.
Source refresh dates: Some dates unavailable; see the source-date panel.
What's tracked: Stored permit, spud, producing-well and DUC records, plus operator, county and formation summaries. Summary fields labeled 24mo or 90d refer to the source refresh window, not a rolling window ending today. Elapsed-day fields also reflect the stored refresh; compare source dates and individual event dates before comparing records.
Disclaimer: Data is provided as a public-service reference. Buckhead Energy is not affiliated with the operators listed unless explicitly stated.
Top 100 Illinois Operators Leaderboard
Illinois Formations & Plays Directory
Top 500 Producing Wells in Illinois
All Recent Illinois Drilling Permits
All Recently Spudded Illinois Wells
All Newly Producing Illinois Wells
Illinois County Drilling Activity Rankings
This snapshot ranks 100 stored Illinois operator records by well count. It does not establish the total number of operators statewide. See the Top Illinois Operators leaderboard and the operator source refresh dates below.
The permit table contains 456 stored records. The permit source refresh dates below identify when those records were loaded; this is not a live permit count.
The stored Illinois summaries contain 5 formations and 102 counties. The tables below list the leading entries, and the source-date panel records each summary table’s refresh dates.
Some source refresh dates are unavailable. The source-date panel identifies the gaps; missing source records are not presented as verified zero counts.
Look up your operator in the operator directory to see their activity, then request a free written offer based on your specific tract, operator, formation, and decimal interest.
State: Illinois
Operators: 100
Counties: 102
Formations: 5
Stored permits: 456
DUCs: —
Source refresh dates: —
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