Canada's Biggest Refinery Sets Fall Maintenance as Northeast Fuel Markets Stay Tight

The Refinery and the Turnaround

Irving Oil runs the biggest oil refinery in all of Canada, and it sits in Saint John, New Brunswick. That plant handles about 300,000 barrels of crude every day, turning it into gasoline, diesel, and heating oil. A lot of that fuel heads south into the northeastern United States, where states like Maine and Massachusetts depend on it.

Irving plans to run its annual fall turnaround, called Operation Osprey, from September 8 to November 18, roughly two and a half months. During a turnaround, some units are taken down for maintenance while others keep operating as normal, so production continues, including diesel.

Maintenance work like this is routine for refineries. But the timing here is not great.

The Saint John refinery has been a critical fuel source for the Northeast for decades. During its 2024 turnaround, which lasted five weeks, regional fuel prices saw temporary spikes.

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Already Tight Fuel Markets

Oil markets were already feeling squeezed before this news. The US-Israeli war on Iran has disrupted flows in a key oil region. Russia's war on Ukraine has been shaking up global energy supplies for years. Together, those conflicts have kept fuel inventories lower than usual.

Right now, the average price at the pump across the United States is above $5 per gallon. Crude oil itself is trading at $82.49 per barrel. Those are elevated numbers by historical standards, and they reflect a market where supply is struggling to keep up with demand.

So even reduced output from some units at a key Northeast supplier matters. Less supply in an already tight market usually means higher prices at the pump. That is simple economics.

What It Means for Your Wallet

The Northeast does not just use gasoline and diesel from this plant. It also gets a lot of its heating oil from the Saint John refinery. And the maintenance runs into the start of heating season.

Heating oil demand typically picks up as temperatures drop, which pushes inventories lower and prices higher. That happens every year. If maintenance trims output from a key supplier during part of that period, the seasonal squeeze could be tighter than usual.

So what does that mean for you? If you live in the Northeast, you might want to keep an eye on heating oil prices this fall. The maintenance could add to the normal winter bump. And for anyone filling up a gas tank, expect that the pressure on prices is not going away anytime soon.

This is not a crisis - just a reality check. Part of a key supplier's operations is down for maintenance, and the market already has little spare supply. Whether that pushes pump prices higher or just keeps them from falling depends on a lot of factors. But the risk is real enough that anyone who relies on heating oil in the Northeast should plan for a pricier winter.

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Correction (September 25, 2026): An earlier version of this article said the Saint John refinery would halt operations and go offline. Irving Oil says that during a typical turnaround, including Operation Osprey, some units undergo maintenance while others continue to operate as normal, allowing production to continue, including diesel. The following lines were updated:

• Headline: "Canada's Biggest Refinery Halts Operations, Squeezing Northeast Fuel Supplies" was changed to "Canada's Biggest Refinery Sets Fall Maintenance as Northeast Fuel Markets Stay Tight"
• Summary: "Irving Oil's Saint John refinery in New Brunswick, the largest in Canada, will undergo maintenance from early September to mid November." was changed to "Irving Oil's Saint John refinery in New Brunswick, the largest in Canada, will take some units down for maintenance from early September to mid-November while others keep running."
• Summary: "The shutdown coincides with already strained fuel markets due to global conflicts, with U.S. pump prices above $5 per gallon." was changed to "The maintenance coincides with already strained fuel markets due to global conflicts, with U.S. pump prices above $5 per gallon."
• Section heading: "The Refinery and the Shutdown" was changed to "The Refinery and the Turnaround"
• Body: "Now the plant is going offline for a while. That is roughly a period of about two and a half months." was changed to "Irving plans to run its annual fall turnaround, called Operation Osprey, from September 8 to November 18, roughly two and a half months. During a turnaround, some units are taken down for maintenance while others keep operating as normal, so production continues, including diesel."
• Body: "A refinery shutdown for routine checks and repairs is normal." was changed to "Maintenance work like this is routine for refineries."
• Body: "So when a refinery that supplies a big chunk of the Northeast shuts down for two and a half months, it does not help." was changed to "So even reduced output from some units at a key Northeast supplier matters."
• Body: "And the shutdown runs right into the start of winter." was changed to "And the maintenance runs into the start of heating season."
• Body: "But with one of the region's main suppliers offline for part of that period, the seasonal squeeze could be worse than usual." was changed to "If maintenance trims output from a key supplier during part of that period, the seasonal squeeze could be tighter than usual."
• Body: "The shutdown could add to the normal winter bump." was changed to "The maintenance could add to the normal winter bump."
• Body: "A big piece of the supply chain is taking a break, and the market is already running on thin margins." was changed to "Part of a key supplier's operations is down for maintenance, and the market already has little spare supply."