What it costs to plug a well in Illinois
Reported costs of publicly funded plugging in Illinois, 2022 to 2026: a median of $36,649 per well.
AHigh confidence
The middle of reported costs is $36,649. Most wells cost between $8,148 and $49,088 (the 10th to 90th percentile). The median is typically within 17% of what individual wells cost. It rests on 783 wells.
How Illinois compares
Illinois's median is below the middle of published states ($43,622) and is number 4 from the bottom of the 10 states with a published figure. State differences reflect well depth, terrain, the age of the wells and how each program buys the work, so a higher number does not by itself mean a less efficient program.
Looking only at years with enough data to publish, the median reported cost was $38,917 in 2022 and $35,913 in 2026, a change of -8%. Part of any change is a different mix of wells from year to year, so use the Plugging Cost Index for like-for-like movement.
The wells behind the figure are mostly oil wells.
Funding
Illinois's orphan well program has received at least $19.0 million in federal infrastructure-law grants that we could match in federal award records. Program tracker for Illinois.
The documented backlog
Illinois lists about 3,946 documented orphan wells. At the published range that would cost roughly $32.2 million to $193.7 million to plug, middle estimate $144.6 million. It is an estimate built from the figures above, not a program budget.
Bonds
Compare the cost with what operators must post: bond amounts for Illinois.
Using the figure
These are costs of orphan wells plugged with public money, mostly shallow vertical wells. A deep, horizontal or offshore well, or a well with a collapsed casing, can cost far more. For a specific well, use the estimator; for the full state page, charts and sources see Illinois costs.