Canada's Oil Sands Cut and Irving Refinery Shutdown Test U.S. Gasoline and Diesel Supply
Oil sands maintenance and Irving's Saint John turnaround through November simultaneously tighten the Canadian crude supply that accounts for 60 percent of U.S. crude imports.
Canada supplied an estimated 60 to 63 percent of all U.S. crude oil imports in 2025, with 90.1 percent of its crude exports directed south, according to data published Wednesday (2026-09-23). Those numbers define a supply relationship where disruption on the Canadian side has no obvious substitute at comparable scale.6
Two such disruptions arrived simultaneously in September. Rystad Energy estimated, as reported by Bloomberg during the week of August 24 (2026-08-24), that oil sands maintenance would reduce Canadian crude production by roughly 300,000 barrels per day in September. Under normal conditions, Canada sends approximately 4 million barrels per day of heavy crude to U.S. refiners — the Rystad estimate represents a 7.5 percent reduction from that baseline.4
Irving Oil's Saint John, New Brunswick facility adds to the picture. Canada's largest oil refinery, with a processing capacity of around 300,000 barrels per day, started a planned turnaround in early September, with a restart expected only in mid-November, according to the company's website. The plant is a key refined products supplier to the northeast United States.2
NYMEX RBOB gasoline futures and NYMEX heating oil — a standard diesel proxy — both declined on Wednesday (2026-09-23). RBOB settled at $3.59 per gallon, down 0.28 percent; heating oil closed at $4.79 per gallon, off 0.83 percent. Both fell on a day when the two Canadian disruptions were simultaneously in effect, moving counter to what the supply constraint would suggest.2,4
Canada's current position in U.S. crude supply is the product of a two-decade structural shift. U.S. crude imports from OPEC fell 84 percent between 2008 and 2025, from 5.42 million barrels per day to 0.86 million barrels per day, according to data published by Yahoo Finance on September 17 (2026-09-17). Canada absorbed most of that gap, delivering 3.91 million barrels per day to U.S. refiners in 2025 — more than 4.5 times the OPEC volume. Domestic shale added the rest: U.S.-sourced crude supply climbed from a low of 4.98 million barrels per day in 2007 to 9.67 million barrels per day by 2025.5
That history gutted the substitution buffer. Venezuela, which exports heavy crude compatible with the same refinery configurations as Canadian oil sands barrels, ran at 1.16 million barrels per day in August 2026, slightly below June's 1.2 million barrels per day as PDVSA reduced storage withdrawals, Reuters reported. At that rate, Venezuela covers less than 30 percent of Canada's normal daily shipments to U.S. refiners.4
ICE Brent crude front-month settled at $103.00 per barrel and NYMEX WTI front-month at $92.24 per barrel on Wednesday (2026-09-23), a spread of roughly $10.75. The Brent premium reflects, in part, the Strait of Hormuz having been effectively closed for more than ninety days as of early June (2026-06-04), the Atlantic Council noted. WTI's domestic discount suggests North American-specific supply — including Canadian volumes — has not registered a meaningful premium relative to the international benchmark gap.1
U.S.-Canada energy trade totaled $137 billion in 2025, per U.S. Census Bureau data, falling 11 percent on lower commodity prices. Crude oil made up 69 percent of the combined value. U.S. energy imports from Canada reached $111 billion; U.S. energy exports north totaled $26 billion.3
Irving's turnaround through mid-November falls precisely on the period when northeast U.S. heating oil demand begins to build. The plant's 300,000 barrel-per-day absence leaves the region dependent on product from longer supply routes. October loading data from the oil sands will be the first signal of whether Canadian volumes recover toward the 4 million barrel-per-day normal; Irving's mid-November restart schedule is the second piece of the supply equation for northeast U.S. fuel markets as winter arrives.2,4