EUR (Estimated Ultimate Recovery)
The total oil or gas a well is expected to produce over its life, from first flow to plug-and-abandon. Usually stated in barrels or Mcf.
Estimated ultimate recovery, or EUR, is the total volume a well is forecast to produce across its entire life. It is the area under the decline curve — past production already on the books plus the remaining reserves projected forward. EUR is quoted in barrels of oil or Mcf (thousand cubic feet) of gas.
EUR is an estimate, not a measurement, and it changes as a well ages and real data replaces the forecast. Early in a well's life the number leans on type curves from nearby wells; later it tightens as actual volumes come in. Engineers and reserves auditors revise it over time.
For a buyer, EUR sets the ceiling on how much royalty a well can ever pay. A bigger EUR with steady production supports a higher purchase price. Pair it with current rates and decline rate when you weigh a deal.