Understanding Estimated Ultimate Recovery (EUR) in the Oil and Gas Industry

Understanding Estimated Ultimate Recovery (EUR) in the Oil and Gas Industry

4 Min.

Estimated Ultimate Recovery (EUR) is a vital concept in the oil and gas industry, representing the amount of recoverable oil or gas from a reserve or well. EUR is classified into three categories: Proven Reserves, Probable Reserves, and Possible Reserves, each based on the likelihood of recovery. Oil prices and technological advancements can lead to a reclassification of reserves. EUR is essential for oil companies to make rational investment decisions.


Estimated Ultimate Recovery is a fundamental term within the oil and gas sector. It serves as a pivotal metric used to estimate the quantity of oil or gas that can potentially be extracted from a reserve or well. Understanding EUR is crucial for decision-making in drilling projects and the evaluation of oil reserves' economic viability.

EUR Calculation

The calculation of EUR is a versatile process, with methods and units varying depending on the specific project or study. Diverse techniques can be employed to determine EUR, but the overarching goal remains the same - to assess the recoverable resources accurately.

Categories of EUR

EUR is divided into three distinct categories, each indicating the likelihood of successful oil recovery based on current technology:

  1. Proven Reserves: In this category, there is a greater than 90% chance that the oil will be successfully extracted. These reserves are considered highly likely to be recoverable.
  2. Probable Reserves: For probable reserves, the chance of successful oil recovery is greater than 50%. These reserves have a significant likelihood of being extracted.
  3. Possible Reserves: In this category, the likelihood of recovering oil is substantial, but it falls below the 50% mark. These reserves carry a lower probability of successful extraction.

Reclassification of Reserves

It's important to note that the status of reserves within an oil field can change over time. Part of the probable and possible reserves can be reclassified as proven reserves due to various factors. These factors include advancements in oil recovery methods and techniques, as well as fluctuations in oil prices.

For example, when oil prices rise, the economics of oil recovery improve. Reserves that were previously too costly to extract at lower prices become economically viable. This leads to the reclassification of reserves from probable or possible to proven. Conversely, if oil prices fall significantly, the probability of extracting certain reserves diminishes. As a result, reserves may be reclassified from proven back to probable or even possible, reflecting their decreased economic feasibility.

EUR's Role in Valuing Oil Reserves

EUR plays a pivotal role in the evaluation and valuation of oil reserves. Without an accurate estimate of EUR, oil companies would be unable to make sound investment decisions. These decisions involve assessing the Net Present Value (NPV) of an oil drilling project.

To arrive at an accurate valuation, several key inputs are required:

  • EUR: Perhaps the most critical input, EUR represents the ultimate amount of oil that can be produced from a given reserve or well.
  • Cost of Production: This encompasses the expenses associated with bringing the first barrel of oil to production, which is a critical factor in project economics.
  • Long-term Oil Prices: Predicting the long-term price of oil is essential as it significantly influences the economic viability of the project.
  • Cost of Capital: The cost of financing the project is crucial to understand the overall cost structure.

The valuation of oil reserves, often performed through NPV analysis, hinges on these inputs. Accurate estimation of EUR is essential to make informed investment decisions, as it directly impacts the assessment of the potential value of oil reserves.


Estimated Ultimate Recovery is a key concept in the oil and gas industry, representing the potential for oil or gas extraction from a reserve. It is divided into three categories: Proven Reserves, Probable Reserves, and Possible Reserves, based on the likelihood of successful recovery. Reclassification of reserves can occur due to technological advancements and oil price fluctuations. EUR is crucial for valuing oil reserves and assessing the economic viability of drilling projects. Accurate estimation of EUR is essential for informed investment decisions and calculating the Net Present Value of potential reserves.

Net Present Value (NPV)
Estimated Ultimate Recovery (EUR)
Follow us
Hexn operates under HEXN (CZ) s.r.o. and HEXN Markets LLC. HEXN (CZ) s.r.o. is incorporated in the Czech Republic with the company number 19300662, registered office at Cimburkova 916/8, Žižkov, Praha. HEXN (CZ) s.r.o. is registered as a virtual assets service provider (VASP). HEXN Markets LLC is incorporated in St. Vincent and Grenadines with the company number 2212 LLC 2022, registered office at Beachmont Business Centre, 379, Kingstown, Saint Vincent and the Grenadines