# Illinois Oil & Gas Formations and Plays Directory
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> Every active Illinois oil and gas formation and play, ranked by well count, with the top operators and primary counties for each. Compiled from IDNR well records, refreshed monthly. CC BY 4.0.

**URL:** https://www.buckheadenergy.com/formations-illinois
**Source:** Buckhead Energy (https://www.buckheadenergy.com/)
**Generated:** 2026-08-02 (heuristic; server-side extraction)

## Answer
Quick answer: The most-targeted oil and gas formations in Illinois are the Illinois Basin, Wisconsin Arch, Michigan Basin, New Albany and Lake Michigan, led by the Illinois Basin with 199,282 wells on record. Ranked by well count across 5 tracked formations from Illinois Department of Natural Resources (IDNR) well-header records (as of 2026-08-02) and refreshed monthly.

## Dataset
**Name:** Illinois Oil & Gas Formations and Plays Directory

Complete directory of every active oil and gas formation and play in Illinois, with well counts, active operator counts, total drilled lateral footage, recent permit volume, and the top operators and counties for each formation.

**Variables measured:**
- Formation / Play Name
- Well Count
- Active Operators
- Total Lateral Footage (feet)
- Recent Permits (24 Months)
- Top Operators
- Top Counties

## Page Outline
- The Illinois Oil & Gas Formations & Plays Directory
  - About This Data
  - Frequently Asked Questions
  - Know What Formation Underlies Your Minerals?
  - Related Operator Intelligence

## Related Pages
- [Illinois Oil & Gas Industry Snapshot Dashboard](https://www.buckheadenergy.com/illinois-oil-gas-industry-snapshot)
- [Top Illinois Operators Leaderboard](https://www.buckheadenergy.com/top-operators-illinois)
- [Illinois Drilling Activity Report (permits, DUCs, spuds)](https://www.buckheadenergy.com/illinois-drilling-activity-report)
- [US Mineral Market Activity Index (all 11 states ranked 0–100)](https://www.buckheadenergy.com/us-mineral-market-activity-index)
- [US Mineral & Drilling Activity Index (national rollup)](https://www.buckheadenergy.com/us-drilling-activity-index)
- [Texas Industry Snapshot (largest producing state)](https://www.buckheadenergy.com/texas-oil-gas-industry-snapshot)
- [Oklahoma Industry Snapshot](https://www.buckheadenergy.com/oklahoma-oil-gas-industry-snapshot)
- [Largest US Operators — National Leaderboard](https://www.buckheadenergy.com/top-operators-us)
- [Browse the Full Operator Directory](https://www.buckheadenergy.com/operators)
- [Live Oil & Gas Prices (WTI + Henry Hub)](https://www.buckheadenergy.com/oil-gas-prices)
- [Sell Your Illinois Mineral Rights](https://www.buckheadenergy.com/sell)
- [How to Sell Mineral Rights (Step-by-Step)](https://www.buckheadenergy.com/2026/how-to-sell-mineral-rights)
- [Oil & Gas Market Data Hub (all dated datasets)](https://www.buckheadenergy.com/oil-gas-market-data)

## About Buckhead Energy
Buckhead Energy is a direct buyer of oil & gas mineral rights and royalty interests across 33 U.S. states. We provide free written offers within 24-48 hours, with closings in 30-45 days. Family-owned and operated since 2007, A+ BBB rated.

**Sell mineral rights:** https://www.buckheadenergy.com/sell
**Operator directory:** https://www.buckheadenergy.com/operators