Oil Reserves History: US Reserves Since 1963
US crude oil proved reserves have swung from 34,128 million barrels in 1963, through a four-decade decline to a low near 20,554 million in 2008, then more than doubled in the shale era to 45,951 million barrels by year-end 2024. The table and chart below trace six decades of US reserve history, plus the two events that reshaped world reserve totals.
The Shale Boom, in One Number
Four decades of decline
- US proved reserves peaked early at 43.0 billion barrels in 1970, then fell almost every year for nearly four decades as conventional fields matured and drilling failed to keep pace with production.
- By 2008, reserves had fallen to 20.6 billion barrels — less than half the 1970 level — and "peak oil" was the consensus framing for US production.
- None of this reflected the oil running out. It reflected which oil was economic to produce with the technology and prices of the time.
Then shale rewrote the story
- Horizontal drilling and multi-stage hydraulic fracturing — see what is fracking — turned shale formations like the Permian Basin and Bakken from source rock into producible reservoirs.
- Reserves more than doubled from the 2008 trough to a peak of 48.3 billion barrels in 2022, even as the US simultaneously became the world's largest crude producer.
- The one sharp reversal, 2020, was a price-driven accounting write-down (see FAQ) — reserves recovered the following year as prices did.
US Crude Oil Proved Reserves by Year
| Year | Reserves (million bbl) | Reserves (billion bbl) |
|---|---|---|
| 2024 | 45,951 | 46.0 |
| 2023 | 46,422 | 46.4 |
| 2022 | 48,321 | 48.3 |
| 2021 | 44,418 | 44.4 |
| 2020 | 38,212 | 38.2 |
| 2019 | 47,172 | 47.2 |
| 2018 | 47,053 | 47.1 |
| 2017 | 41,990 | 42.0 |
| 2016 | 35,213 | 35.2 |
| 2015 | 35,230 | 35.2 |
| 2014 | 39,933 | 39.9 |
| 2013 | 36,520 | 36.5 |
| 2012 | 33,403 | 33.4 |
| 2011 | 28,950 | 29.0 |
| 2010 | 25,181 | 25.2 |
| 2009 | 22,315 | 22.3 |
| 2008 | 20,554 | 20.6 |
| 2005 | 23,019 | 23.0 |
| 2000 | 23,517 | 23.5 |
| 1995 | 23,548 | 23.5 |
| 1990 | 27,556 | 27.6 |
| 1985 | 29,869 | 29.9 |
| 1980 | 31,335 | 31.3 |
| 1975 | 36,015 | 36.0 |
| 1970 | 42,979 | 43.0 |
| 1963 | 34,128 | 34.1 |
Crude oil and lease condensate proved reserves, year-end each year. Source: EIA, Annual Reserves Report (Form EIA-23L). See the current state-by-state breakdown on oil reserves by state.
World Reserves: Two Reclassifications That Rewrote the Totals
Approximate world total (billion barrels)
- 2000: ~1,105 billion barrels
- 2005: ~1,195 billion barrels
- 2010: ~1,380 billion barrels
- 2015: ~1,655 billion barrels
- 2020: ~1,732 billion barrels
- 2023: ~1,740 billion barrels
Approximate, rounded figures for trend illustration — OPEC ASB and BP Statistical Review differ on exact totals depending on how Canadian oil sands and Venezuelan extra-heavy crude are counted. See the current, sourced country-by-country table on oil reserves by country.
What actually happened
- 2002-2004: Canada reclassifies Alberta oil-sands bitumen as proved reserves under then-current prices/technology, adding well over 150 billion barrels overnight in official statistics — reserves didn't grow underground, the accounting did.
- 2013: Venezuela certifies extra-heavy crude in the Orinoco Belt as proved reserves, adding roughly 86 billion barrels in a single year and pushing Venezuela past Saudi Arabia into the #1 spot by reserves — even as its actual production kept falling.
Oil Reserves History FAQ
How much have US oil reserves grown since the shale boom?
US crude oil proved reserves roughly more than doubled from 20,554 million barrels at year-end 2008 to 45,951 million barrels at year-end 2024 — more than doubling in a decade and a half, driven almost entirely by shale plays like the Permian Basin and Bakken becoming economic to drill at scale.
When did US oil reserves peak?
The highest year-end total in this series was 48,321 million barrels in 2022, reached as shale drilling accelerated through the post-pandemic price recovery. Reserves have since eased back toward 45,951 million barrels (2024) as revisions and production outpaced new bookings in some years — normal year-to-year variation, not a reversal of the shale-era trend.
Why did US reserves fall so sharply in 2020?
Oil prices collapsed in spring 2020 as COVID-19 demand destruction met a Saudi–Russia price war, briefly sending WTI negative. Proved-reserves rules require using trailing 12-month average prices, so a large share of shale acreage that was economic at $50–60/bbl fell below the cutoff and had to be written down — reserves fell from 44.4 billion barrels (2019) to 38.2 billion (2020) even though the oil never left the ground.
Why did world reserves jump so much in the 2000s and 2010s?
Almost entirely from reclassification, not new discovery. Canada began counting Alberta oil-sands bitumen as proved reserves in the early 2000s, and Venezuela certified its extra-heavy Orinoco Belt crude in 2013 — together adding several hundred billion barrels to world totals on paper, years before most of that oil was ever produced.