Mexico locks in definitive anti-dumping duties of 1.93 dollars per kilogram on Chinese hollow aluminium profiles and 1.72 dollars on US product, capping an eighteen month investigation that lands squarely in the middle of the country’s broader confrontation with Chinese metals overcapacity.
MEXICO CITY, September 7, 2026. Mexico has closed one of the most closely watched trade remedy cases on its docket, imposing definitive anti-dumping duties on hollow aluminium profiles from China and the United States and signalling, once again, that the Sheinbaum administration intends to defend its metals sector with the full toolkit of trade law rather than tariff decrees alone.
The final resolution of the anti-dumping investigation into imports of perfiles huecos de aluminio, hollow aluminium profiles, was published in the evening edition of the Diario Oficial de la Federación (DOF) on September 4, 2026, under registry code 5798041. Signed on August 27 by Economy Secretary Marcelo Luis Ebrard Casaubon, the resolution took effect the day after publication and applies to the covered goods regardless of the country from which they are shipped.
The operative numbers are stark. Imports originating in China now face a definitive duty of 1.93 US dollars per kilogram. Imports originating in the United States face 1.72 dollars per kilogram. Both figures are higher than the provisional duties of 1.88 and 1.62 dollars per kilogram, respectively, that the Ministry of Economy imposed at the preliminary stage on December 31, 2025. According to the resolution, the definitive duties are equivalent to the dumping margins calculated in the final phase of the investigation, and they apply to both definitive and temporary imports entering under tariff item 7604.21.01 of Mexico’s TIGIE tariff schedule “or any other” tariff line, a formulation designed to foreclose evasion through reclassification.
For international trade professionals, the case is best read as another brick in the wall Mexico is building against low priced Chinese aluminium, with the United States as a secondary, if legally coequal, target. The resolution arrives amid a global scramble to contain Chinese metal surpluses, an active renegotiation dynamic under the USMCA review, and a Mexican industrial policy, Plan Mexico, that has made import substitution and tariff defense of domestic manufacturing an explicit national objective.
What the resolution says
The investigation was triggered by a complaint filed on September 30, 2024 by two Mexican producers, Cuprum, S.A. de C.V. and Indalum, S.A. de C.V., which the Ministry of Economy recognized as the domestic industry for the product. Mexican press coverage of the parallel aluminium cases resolved the same week, including reporting by El Sol de México, has described the two companies as accounting for roughly two thirds of national production of the relevant aluminium extrusions.
The Ministry initiated the investigation on March 5, 2025, fixed the dumping investigation period as July 1, 2023 to June 30, 2024, and set the injury analysis period as July 1, 2021 to June 30, 2024. A preliminary resolution followed on December 31, 2025, with immediate provisional duties. Technical information meetings were held in January 2026, a public hearing took place on June 12, 2026, and the Foreign Trade Commission issued a favorable majority opinion on August 6, 2026. The Ministry expressly invoked Article 5.10 of the WTO Anti-Dumping Agreement, citing the volume and complexity of the record and multiple extensions granted to parties, to justify using the full eighteen month window allowed for concluding the case.
The product scope covers hollow aluminium profiles, alloyed or unalloyed, of any dimension, form or figure, finished or unfinished, including painted and anodized product. The resolution describes goods made from 6000 series alloys and 1000 series commercially pure aluminium, in widths from 0.250 to 11.5 inches and lengths from 3 to 16.7 meters, manufactured to standards such as ASTM B221-21 and, for anodized product, DIN 17611. The commercial universe is essentially architectural: window and door profiles, sliding frame elements, curtain wall members, fence and screen components, louvers and similar building products. Following arguments at the final stage, the Ministry confirmed that hollow profiles used in blinds, curtain rails and bathroom enclosures fall within the scope because they share the essential characteristics of the investigated product and can be made by the domestic industry.
The exclusions matter just as much for compliance planning. The resolution states that hollow aluminium profiles for automotive use and for the air conditioning and refrigeration industry have distinct characteristics and chemical composition and are outside the coverage of the investigation. Also excluded are microchannel extrusions and microchannel tubes, flat MPE tubes, zinc coated hollow profiles, hollow profiles subjected to tempering heat treatment, and profiles made from 3000 series aluminium. That tempering carve-out proved decisive for the Mexican tool company Truper, whose technical documentation showed imports of 6000 series profiles with T5 and T6 temper; the Ministry concluded those tempered goods are simply not covered product, even as it declined Truper’s broader request to exclude profiles destined for ladders and other industrial tools.
An injury record built on prices
The heart of the final resolution is its injury and causation analysis, and the numbers the Ministry published are unusually pointed. In its concluding findings, the authority determined that the investigated imports entered with dumping margins of between 1.72 and 1.93 dollars per kilogram and represented 86 percent of total Mexican imports of the product during the investigation period.
Volumes rose steadily. Investigated imports grew 33 percent across the injury analysis period, increasing 16 percent in the second period and a further 15 percent in the investigation period. Their share of Mexico’s apparent national consumption climbed from 28.7 percent to 31.3 percent, a gain of 2.6 percentage points captured directly from domestic producers in a market that was not growing fast enough to absorb both.
Prices did the real damage. The average price of the investigated imports fell 18 percent over the analysis period, and undercutting against the domestic industry’s home market prices deepened from 23 percent in the first period to 26 percent in the second and 33 percent in the investigation period. The imports also undersold third country suppliers by 41, 57 and 50 percent in the same periods, which the Ministry cited to explain why Chinese and US material displaced not only Mexican production but also alternative import sources.
The financial consequences for Cuprum and Indalum, as recorded in the resolution, were severe. Domestic sales prices fell 3 percent in the investigation period and 5 percent across the analysis period, as the producers cut prices to defend share. Revenue from domestic sales dropped 15 percent, then 13 percent, for a cumulative 26 percent decline. Operating results fell 17 percent and then 67 percent, a cumulative collapse of 72 percent, taking the industry’s operating margin from 11.2 percent to 4.2 percent. In one of the more vivid details in the record, the Ministry found that nine customers of the domestic producers cut their purchases of Mexican hollow profiles by 28 percent during the investigation period while increasing their imports from China and the United States by 397 percent.
The Ministry concluded that no other injury factor could account for this deterioration. It also explained why it declined to apply a lesser duty. Although Article 7.4 of the Anti-Dumping Agreement led the authority to extend the provisional duties to six months while it evaluated whether a duty below the dumping margin would suffice to remove injury, the final resolution concluded the opposite: given how low the import prices were, even a duty equal to the full dumping margin “would be insufficient” to fully correct the effect of the dumped imports on domestic prices. The Ministry therefore set the definitive duties at the full calculated margins under Article 9.1 of the Agreement and Article 62 of Mexico’s Foreign Trade Law.
Exporters lose the margins battle
No company on either side of the Pacific earned an individual duty rate, and the procedural history explains why. Four Chinese producer exporters appeared in the case: Foshan City Nanhai Yongfeng Aluminium, Guang Ya Aluminium Industries, Guangdong Haomei New Materials and Mum Group. Five US companies participated: Hydro Extrusion USA, Hydro Precision Tubing USA, Magnode, Merit Aluminum and UACJ Automotive Whitehall Industries.
According to the resolution, the Chinese exporters failed to substantiate their questionnaire responses. None provided documentary support for the accounting systems behind their product codes. Three of the four backed their export databases with a single invoice each, and Guang Ya submitted only a proforma invoice, a document the Ministry dismissed as not definitive of the essential terms of sale. The Ministry also found that transactions Guang Ya attributed to a subsidiary that made “some products” in fact represented 60 percent of its reported exports. Filings the Chinese companies made in February 2026 were rejected as untimely new information rather than complementary evidence, and the authority noted that exporters had 38 business days, including two extensions, to supply normal value data and still did not.
On the US side, the Hydro companies could not corroborate their constructed value submissions, and UACJ Automotive was denied an individual margin for lack of necessary information. The result: country wide rates for everyone, calculated on the basis of the facts available under Article 6.8 and Annex II of the Anti-Dumping Agreement, with the Ministry quoting WTO Appellate Body language from the US Hot-Rolled Steel dispute on the “very high degree of cooperation” required of interested parties.
One methodological point deserves attention from China watchers. The Ministry stated expressly that it made no determination on whether China is a market economy. Normal value was constructed from the cost structure of the Mexican complainants, with an aluminium input reference price drawn from the Aluminium Network website, sourced from Shanghai Metal Market, used strictly as an input cost reference “and not as information corresponding to a surrogate country.” That framing sidesteps the perennial surrogate country fights that have dogged other jurisdictions’ China cases, though it invites its own arguments about constructed value reliability.
Stakeholders on the record
The resolution preserves the positions of the parties, and they sketch the coming compliance disputes. Truper argued that the duties would damage the competitiveness of Mexican companies that rely on imported profiles. The Ministry answered that anti-dumping duties are designed to correct the injurious effects of unfairly priced imports and restore fair competition, affect only those importing at unfair prices, and leave importers free to source hollow profiles from origins not implicated in unfair trade.
Merit Aluminum and its related Mexican importer, Frontera Aluminios, mounted the most consequential challenge, arguing that their temporary imports, aluminium sent to Mexico for anodizing and painting under maquila arrangements and then returned to the United States, with only 0.4 percent sold into the Mexican market, should fall outside the measure. The Ministry rejected the request, holding that temporary imports enter the national market, displace similar domestic product at that moment, and are covered by both the Foreign Trade Law and the Customs Law. The final resolution reiterates that the duties reach temporary as well as definitive imports, language with direct consequences for IMMEX program manufacturers that process aluminium in Mexico for re-export.
Government participation was lopsided. The United States Embassy in Mexico City appeared as an interested party but, according to the resolution, filed no complementary evidence, no comments on the essential facts, and no closing arguments. The government of China was notified and did not appear at all. Neither Beijing nor Washington had issued a formal public response to the final duties as of Monday. Mexican media reported that a senior foreign ministry official, Roberto Velasco, was due in China on September 7 to tend to political and commercial ties strained by Mexico’s recent tariff moves, a reminder that trade defense and diplomacy are now running on parallel tracks.
For the complainants, the outcome is close to a full victory: duties at the full margin, a scope that survived most exclusion requests, and an injury record that will be difficult to unwind on review. Importers of architectural profiles, by contrast, absorbed a duty increase between the preliminary and final stages, an unusual trajectory that reflects the recalculated margins.
The policy backdrop: Plan Mexico and a hardening line
The hollow profiles case did not unfold in a vacuum. On the same September 4 evening edition of the DOF, the Ministry published a separate final resolution, registry code 5797943, imposing a definitive duty of 1.58 dollars per kilogram on solid aluminium profiles and bars from China, a companion case also brought by Cuprum and Indalum. Trade advisory firms including Stratego and customs law blogs flagged the twin resolutions to clients within hours. Taken together, Mexico has now fenced off both the hollow and solid segments of the extrusion market with specific duties in the range of 1.58 to 1.93 dollars per kilogram.
Layered beneath the anti-dumping duties sits Mexico’s most favored nation tariff wall. The resolution itself records that, under the decree modifying the general import tariff and sectoral promotion programs published in the DOF on April 23, 2026, imports under tariff item 7604.21.01 have been subject to a 25 percent duty since April 24, 2026. That decree, analyzed by White & Case as covering 185 tariff lines across new sectors, extends the tariff architecture Mexico began building in 2024, when temporary duties of 5 to 50 percent were applied to 544 tariff lines spanning steel, aluminium, textiles and other sensitive goods. Mexico’s Finance Ministry has projected roughly 51.9 billion pesos in additional 2026 revenue from the broader tariff package aimed principally at Asian imports.
The practical arithmetic for a Chinese exporter is therefore punishing: a 25 percent MFN tariff at the border, plus 1.93 dollars per kilogram in anti-dumping duty, on a product whose competitive appeal was precisely its low price. Because specific duties bite hardest on the cheapest goods, the per kilogram format functions as a steep and regressive ad valorem equivalent at the low end of the market, which is exactly where the Ministry found the injury concentrated.
US suppliers face a different calculus. Their goods generally enter Mexico duty free under the USMCA, so the 1.72 dollar anti-dumping duty is the only barrier, but it is a substantial one for a commodity extrusion. The inclusion of the United States in a Mexican trade remedy case, at the very moment Mexico is lobbying Washington to reduce the 50 percent Section 232 tariff on Mexican steel and aluminium toward something closer to the roughly 10 percent rate granted to the United Kingdom, gives the case an awkward bilateral edge. Reporting around the USMCA review talks, including by Transport Topics and the Rio Times, indicates Washington has pressed Mexico to erect Section 232 style barriers against non North American metals, effectively asking Mexico to align with the US containment strategy on Chinese steel and aluminium. A Mexican duty on US aluminium cuts against that harmonizing current, even if it is the product of an independent quasi judicial process rather than a policy choice.
The global aluminium chessboard
The deeper context is Chinese supply. China produces and consumes more than half of the world’s aluminium, and its primary output reached 45.02 million tonnes in 2025, pressing against the 45 million tonne capacity cap Beijing set in 2017, according to industry analyses published by Asia Society Policy Institute and Recycling Today. Chinese exports of unwrought aluminium and aluminium products fell 8 percent in 2025 to about 6 million tonnes as tariffs and anti-dumping duties in multiple jurisdictions restricted outlets. Every new measure, from the US Section 232 aluminium tariff, raised to 25 percent in March 2025 and then to 50 percent effective June 4, 2025, to European Union trade defense actions on Chinese extrusions, redirects displaced metal toward the remaining open markets. Mexico, with a large construction sector, a peso denominated price sensitive market and duty free access to the United States, was an obvious destination.
That is also why the anti-circumvention features of this resolution matter beyond Mexico. The duties apply regardless of the country of shipment, reach any tariff line under which the goods might be entered, and cover temporary imports that enter under processing programs. Under Article 66 of the Foreign Trade Law, importers can escape the duty only by proving the goods originate somewhere other than China or the United States, using Mexico’s non-preferential origin certification rules dating to a 1994 accord and its many amendments. For US authorities perennially worried that Mexico could serve as a conduit for Chinese aluminium into North America, a Mexican measure that polices origin at its own border is quietly reassuring, whatever the irritation of the duty on US product itself.
What importers and supply chains should do now
For companies moving aluminium extrusions into Mexico, the compliance workload starts immediately. The duties took effect September 5. Importers should map their purchase orders against the scope definition, paying particular attention to the boundary lines the resolution draws: architectural hollow profiles are in; automotive, HVAC and refrigeration profiles, microchannel products, zinc coated goods, tempered profiles and 3000 series material are out. Because exclusions attach to the product and not to the importing company, documentation, mill certificates, alloy and temper designations and technical sheets will decide individual entries. The Truper episode shows both the value of technical evidence and the cost of missing procedural deadlines.
Manufacturers operating under IMMEX and similar temporary import regimes should assume the duties apply to their inflows of covered product and model the cash flow impact, since the Ministry has now twice rejected the argument that maquila destined material is outside the measure. Buyers who relied on the price gap over domestic product, which reached 33 percent against Mexican prices and up to 57 percent against third country imports, will find that arbitrage largely closed; procurement teams are already scanning alternative origins, and the resolution pointedly notes that importers remain free to source from countries not implicated in unfair pricing.
Exporters have narrower options. With country wide rates set on facts available, Chinese and US producers seeking individual treatment would need to await a review procedure and arrive with the documentary rigor the Ministry found lacking, complete accounting support, full invoice trails and verified cost data. Legal challenges are possible before Mexico’s specialized courts or through USMCA and WTO channels, and the duty on US product could yet surface as a bargaining chip in the ongoing USMCA review, where the fourth round of talks is scheduled for September, according to Mexico Business News.
The five year clock on the duties now begins, with sunset review to follow. On the evidence of the last eighteen months, in which Mexico has raised MFN tariffs on aluminium, finalized twin extrusion cases in a single evening gazette and absorbed sustained pressure from Washington to harden its posture toward Chinese metals, few in the trade bar expect Mexican trade defense to soften before then. The DOF text, including the full procedural record and scope language, is the controlling source for entry by entry determinations, and companies with borderline products should read it closely.