A fill-up that cost $300 in January now costs $425, and the same thing is happening at marinas from the Gulf Coast to the Great Lakes.
It's already starting to change what boaters do this season.
Average regular gas in Alabama runs around $3.85 a gallon, while diesel sits above $5.43, with both well above where they were a year ago.
The cause is the U.S. and Israel's war with Iran, which kicked off in late February and has pushed oil prices higher across the board.
Smaller boats hold around 40 gallons, while larger offshore rigs can carry 300 to 400, which means a single offshore fill-up can run more than $2,000 at current prices.
"Fishing season is just around the corner and I think a lot of boats are going to remain tied up," Dauphin Island local Michael Kennedy told Fox 10, adding that fuel costs for his boat are running close to double what they were last year.
The recreational boat industry was already soft, with sales down 8% to 10% last year, and pre-owned boats made up 80% of total 2025 sales as buyers pulled back from new purchases.
This year, the trend is shifting again, with buyers leaning toward smaller, trailerable boats and personal watercraft that are cheaper to buy and run.
Boat clubs and shared-access models are also picking up speed as buyers look for ways to get on the water without owning the asset.
Charter operators are passing fuel costs through to customers, and some marinas are seeing fewer trips per customer than last year.
Brunswick (BC), the parent of Mercury Marine, makes most of its money on engines and parts that depend on people actually using their boats, so falling trip volume hits its revenue line directly.
Yamaha and Polaris (PII) both sell into the same recreational segment, with Polaris also exposed through personal watercraft.
The shrimp and commercial fishing fleets are also being squeezed, with operators along the Gulf Coast saying fuel costs are now their single biggest concern heading into the busy season.
For investors, the read-through is straightforward.
Watch: engine sales, dealer inventory, and Q2 commentary from each name on whether buyers are trading down or sitting out the season.
Brunswick reported in its Q1 2026 release that U.S. boat retail unit sales fell about 9% in 2025, and its 2026 net sales guidance of $5.6 to $5.8 billion assumes only a flat to slightly higher industry.
Dealer floorplan loans are another stress point, since unsold boats sitting on lots tie up cash for both dealers and the lenders behind them.
The marina business is also worth watching, since slip rentals and dock fees lean on actual usage, not just ownership.
Marine insurance is another quiet pressure point, with premiums up across the board even as fewer boats hit the water - which means owners are paying more to cover assets that are spending more time tied up.
The National Marine Manufacturers Association had projected 2026 sales similar to 2025, but that view assumed fuel prices would ease, and they haven't.
Watch charter bookings and how dealers price summer inventory, because both are leading signals for how the rest of the season plays out.