Canada 50% Auto Tariff: What It Means for Toyota, Honda and Century Aluminum

President Trump said on 24 August 2026 that the United States will tax Canadian cars, trucks, automotive parts and steel at 50% from 1 January 2027, killing the tentative deal that would have halved the Section 232 tariff on Canadian metals. [1][2]

That collapsed deal would have cut the tariff on Canadian vehicles from 25% to 15% and the tariff on steel and aluminium from 50% to 25%. [1] The most substantive change in the new plan is that automotive parts enter the tariff base for the first time: the United States imported US$11.01bn of Canadian motor-vehicle parts in 2025. [3]

The day's price reaction was concentrated on the US side. Ford (F) fell 3.40%, Magna (MGA) — Canada's largest parts supplier — fell 7.19%, and trucking company J.B. Hunt (JBHT) fell 5.65%. [4] Metals moved the other way: Alcoa (AA) fell 4.74% while Cleveland-Cliffs (CLF) rose 0.27%. [4] Canada will impose retaliatory tariffs on US steel from 8 September. [2]

Who pays, and where Canadian vehicle assembly actually sits

A tariff of this kind is collected at the US border on the declared customs value of the goods, and the payer is the US importer of record. Parts are dutiable on their full value at every crossing, so components that move back and forth between the two countries are taxed each time.

Canadian vehicle assembly does not belong to the Detroit three. Toyota's Ontario capacity is 500,000 units a year, building the RAV4 and the Lexus NX and RX. [5][6] Honda builds about 400,000 vehicles a year in Alliston, Ontario, roughly three-quarters of which are exported to the United States. [7][8]

The aluminium price has a structure worth knowing. A US aluminium price is the London Metal Exchange benchmark plus a delivered surcharge called the Midwest premium. That premium contains the tariff, so it rises as the tariff rises. Alcoa's FY2025 10-K states that the Midwest premium rose 211% year on year, largely reflecting the Section 232 tariff on Canadian aluminium going from 25% to 50% during 2025. [9]

From vehicles to parts to the aluminium premium

The first link is the new parts line. US$11.01bn of annual imports at 50% is roughly US$5.5bn a year of duty, and it lands on US importers. [1][3]

The second link is vehicles. Moving the rate from 25% to 50% is a per-unit tax on assembling in Canada, and Canadian assembly capacity is concentrated in the Toyota and Honda plants in Ontario. [5][7]

The third link is timing. The effective date is more than four months out, so the fourth quarter of 2026 is a window to pull Canadian parts and vehicles into the US, followed by the reverse.

The fourth link returns to metals. With the deal dead, the Section 232 tariff on Canadian metal stays at 50% rather than falling to 25%, and the wall that holds up the Midwest premium stays in place. [9] The two sides of that wall differ: a producer with Canadian smelting capacity selling into the US pays the duty, while a smelter whose capacity is entirely inside the United States collects the premium with no offsetting tariff cost.

Second-order exposures

Toyota (7203.T) is a Japanese automaker on the "assemble in Canada, sell into the US" link. Its own plant fact sheet puts Ontario capacity at 500,000 units a year. [5][6] Assuming roughly 400,000 US-bound units at an average wholesale value of about US$40,000 — neither figure is disclosed, so both are estimates — the incremental 25 percentage points are worth roughly US$4bn a year, about 16% of the ¥3.77tn operating income Toyota reported for FY2026. [10] What may come under pressure is North American operating income; how much can be passed through in price is the open question. Toyota closed down 0.22% in Tokyo on the day, and its US ADR (TM) fell 1.79%. [4]

Honda (7267.T) sits on the same link. Honda Canada's site states that Alliston builds 400,000 vehicles a year, and a separate report puts US-bound exports at roughly three-quarters of that, about 300,000 units. [7][8] At an assumed average wholesale value of about US$31,000, the incremental 25 percentage points are worth roughly US$2.3bn a year, against the ¥650bn FY2027 operating-profit guidance Honda raised on 5 August. [11] What may come under pressure is its operating margin. Honda is weighing an eighth North American assembly plant; if capacity moves, the effect changes from a recurring annual cost into one-off capital expenditure. [12] Honda closed down 0.34% in Tokyo, and its ADR (HMC) fell 2.34%. [4]

Century Aluminum (CENX) is a US primary aluminium smelter on the receiving side of the premium, with 450,000 tonnes a year of US capacity — Sebree at 220,000 and Mt. Holly at 230,000. [13] On its 6 August call the company put the Midwest premium at about US$1.11/lb, guided Q3 to US$1.09/lb, and guided Q3 adjusted EBITDA to US$325-345m. [14] Halving the Canadian rate would, on the arithmetic, remove up to about US$0.37/lb, worth as much as US$367m of annual EBITDA on 450,000 tonnes; with the deal dead, that stays. What may benefit is its realised premium and segment EBITDA. The stock fell 3.10% on 18 August, 4.56% on 19 August and a further 0.59% on 24 August, closing at US$43.66 against a US$47.12 close on 17 August. [4]

What would confirm or break this chain

The nearest checkpoint is Canada's retaliation list on 8 September, and whether it taxes US steel and aluminium exports. [2] On the aluminium leg, watch whether weekly Midwest premium prints hold near US$1.09/lb, and whether Century Aluminum's Q3 result in late October delivers the guided realised premium and adjusted EBITDA. [14]

On the vehicle leg, the companies speak for themselves: whether Toyota and Honda put the 1 January 2027 rate into guidance on their quarterly calls in early November 2026 and early February 2027, or announce moving Ontario volume to a US plant. [11][12]

Three things would break the chain. First, a revived deal or a metals carve-out that cuts the Canadian metals rate to 25% before 1 January 2027 — not a tail risk, given that the same deal was described as tentative five days earlier. [15] Second, the 1 January date slipping, or USMCA-compliant content being excluded from the parts line. Third, disclosure by Century Aluminum that it has sold forward or hedged the 2027 Midwest premium, in which case the rent accrues to the counterparty rather than to shareholders. [13]

This is a map of possible transmission chains, not a stock recommendation.

Sources

[1] The Spokesman-Review, 24 August 2026 — https://www.spokesman.com/stories/2026/aug/24/trump-threatens-50-tariffs-on-all-cars-and-trucks-/ [2] CNBC, 24 August 2026 — https://www.cnbc.com/2026/08/24/stocks-making-the-biggest-moves-midday-expe-nvda-mstr-hims.html [3] Trading Economics (US Census), 2025 — https://tradingeconomics.com/united-states/imports/canada/parts-accessories-motor-vehicles-headings-8701-8705 [4] Drillr price_volume_history, daily closes, 14-24 August 2026 [5] Toyota USA Newsroom, TMMC fact sheet — https://pressroom.toyota.com/toyota-motor-manufacturing-canada-inc-tmmc-fact-sheet/ [6] TMMC Inc., Toyota manufacturing plants in Canada — https://tmmc.ca/en/toyota-manufacturing-plants/ [7] Honda Canada, manufacturing — https://www.hondacanada.ca/en/manufacturing [8] Motor Illustrated, 24 August 2026 — https://motorillustrated.com/honda-evaluates-u-s-expansion-as-canada-seeks-manufacturing-stability/189987/amp/ [9] Alcoa Form 10-K (FY2025), filed 26 February 2026 [10] Drillr financial_statements, 7203.T, FY2026 [11] Drillr earning_call_summary, 7267.T, 5 August 2026 (FY2027 Q1) [12] Carscoops, 21 July 2026 — https://www.carscoops.com/2026/07/honda-north-america-plant/ [13] Century Aluminum Form 10-K (FY2025), filed 3 March 2026 [14] Drillr earning_call_summary, CENX, 6 August 2026 (FY2026 Q2) [15] Fastmarkets, 19 August 2026 — https://www.fastmarkets.com/insights/european-aluminium-market-watchful-of-proposed-us-canada-tariff-reduction/