Reserve Estimates

OSLO, NORWAY–The United States now holds the world’s largest recoverable oil reserve base–more than Saudi Arabia or Russia–thanks to the development of unconventional resource plays.

Ranking nations by the most likely estimate for existing fields, discoveries and as-of-yet undiscovered fields (proved, probable. possible and undiscovered), the United States is at the top of the list with 264 billion barrels of recoverable oil reserves, followed by Russia with 256 billion, Saudi Arabia with 212 billion, Canada with 167 billion, Iran with 143 billion, and Brazil with 120 billion (Table 1).

TABLE 1

Estimated Global Oil Reserves

Importantly, unconventional plays account for more than 50 percent of remaining U.S. oil reserves, with Texas alone holding more than 60 billion barrels of recoverable oil in shale plays.

The reserves data distinguish between reserves in existing fields and new projects, and potential reserves in recent discoveries and still undiscovered fields. The estimates include crude oil plus condensate.

An established standard approach for estimating reserves is applied to all fields in all countries, so reserves can be compared apple-to-apple across the world, both for OPEC and non-OPEC countries.

Other public sources of global oil reserves are based on official reporting from national authorities, with reserves reported based on a diverse and opaque set of standards. For example, some OPEC countries, such as Venezuela, report official reserves apparently including yet-undiscovered oil, while China and Brazil officially report conservative estimates and only for existing fields.

Total global oil reserves are estimated at 2,092 billion barrels, or 70 times the current production rate of about 30 billion barrels of oil a year. For comparison, cumulatively produced oil through 2015 amounted to 1,300 billion barrels.

Unconventional oil recovery accounts for 30 percent of the global recoverable oil reserves, while offshore fields account for 33 percent of the total. The seven major oil companies hold less than 10 percent of the total recoverable reserve base.

Considering only proved reserves (1P), the study ranks Saudi Arabia at the top with 70 billion barrels, followed by Russia with 51 billion, Iran with 32 billion, the United States with 29 billion and Canada with 24 billion. Ranked by proved plus probable reserves (P2), Saudi Arabia holds 120 billion barrels, followed by Russia with 77 billion, Iran with 59 billion, Canada with 41 billion and the United States with 40 billion.