how much oil is left in the permian basin

The Permian Basin still has a lot of oil left, but the exact amount depends on what you mean by “left.” A recent U.S. Geological Survey assessment found 1.6 billion barrels of technically recoverable oil in two Permian secondary shales, while older academic estimates for the broader basin suggested tens of billions of barrels could remain in place, with recovery depending on technology and economics.

What that means

• Technically recoverable oil is the amount that could be produced with current methods and known geology, not the total oil underground.

• The January 2026 USGS estimate focused on the Woodford and Barnett shales in the Permian Basin and put recoverable oil at 1.6 billion barrels.

• A much older University of Texas estimate for the broader Permian said 74.5 billion barrels could remain in reservoirs at depletion, reflecting a very different question: oil in place versus oil that can be economically recovered.

Why estimates differ

Different reports count different things. Some measure undiscovered recoverable resources , some measure original oil in place , and others estimate what remains after years of production and current recovery rates.

Practical takeaway

So the short answer is: there is still a large amount of oil left in the Permian Basin, but the best current public estimate for newly assessed, technically recoverable oil is 1.6 billion barrels in selected shales, not the entire basin’s total remaining oil. The basin is still a major U.S. oil region, and recent reporting says production may be nearing a peak even while resources remain.

TL;DR

• Newest USGS figure: 1.6 billion barrels of technically recoverable oil in selected Permian shales.

• Broader legacy estimates: tens of billions of barrels may still remain in the basin, depending on definition and recovery assumptions.

• Best plain-English answer: a lot of oil is still there, but how much can actually be produced is much smaller than the total underground amount.