Buying electrical steel for Mexico: ASTM and AISI grades, 2026 tariffs, CIF quotes to Manzanillo
Mexican transformer and motor makers mostly follow ASTM and AISI grades. This guide gives the Baosteel equivalents, the 2026 tariff changes to check, and how CIF shipments to Manzanillo or Lázaro Cárdenas are quoted.
ASTM and AISI grades and their Baosteel match
Grain-oriented steel is covered by ASTM A876 and non-oriented steel by ASTM A677, but drawings in Mexico still often name the older AISI M-grades (M-3 to M-6 for grain-oriented, M-15 to M-47 for non-oriented). The tables match Baosteel grades by thickness and guaranteed loss class; note that ASTM measures loss at 60 Hz.
| Baosteel | Nippon Steel | thyssenkrupp | AISI |
|---|---|---|---|
| B23R085 | 23ZDKH85 | H085-23 | — |
| B23P090 | 23ZH090 | H090-23 | — |
| B23P100 | 23ZH100 | H100-23 | H-0 |
| B27P100 | 27ZH100 | H103-27 | — |
| B27P110 | 27ZH110 | — | H-1 |
| B23G120 | — | C120-23 | M-3 |
| B27G130 | 27Z130 | C130-27 | M-4 |
| B30G140 | 30Z140 | C140-30 | M-5 |
| B35G155 | 35Z155 | C165-35 | M-6 |
| Baosteel | EN 10106 | AISI |
|---|---|---|
| B35A250 | M250-35A | M-15 |
| B35A270 | M270-35A | M-19 |
| B35A300 | M300-35A | M-22 / M-27 |
| B50A290 | M290-50A | M-15 |
| B50A310 | M310-50A | M-19 |
| B50A350 | M350-50A | M-22 |
| B50A470 | M470-50A | — |
| B50A600 | M600-50A | — |
| B50A800 | M800-50A | — |
| B65A600 | M600-65A | M-45 |
2026 tariffs to check
From 1 January 2026 Mexico raised import tariffs, up to 50%, on many goods from countries without a trade agreement with Mexico, including China; most steel lines were reported at 35%. Mexico also runs anti-dumping cases on Chinese steel and the PROSEC sector programmes, which can lower the duty for registered manufacturers. Ask your customs agent (agente aduanal) for the rate on your exact tariff code and whether PROSEC applies before you order.
Shipping to Manzanillo, Lázaro Cárdenas and Altamira
- Manzanillo and Lázaro Cárdenas on the Pacific are the direct ports from China for central Mexico; Altamira and Veracruz on the Gulf suit the north-east, usually via transhipment.
- Coils in 20-foot containers on fixed saddles; laminations and cores on pallets or in crates with ISPM 15 wood.
- Your importer must be registered in the Padrón de Importadores, and steel may need a sector registration; your agente aduanal will confirm.
How a CIF quotation works
Under CIF (Incoterms 2020) we book the ocean freight and buy cargo insurance to your named port of destination. Risk passes to you when the goods are loaded on board at the Chinese port; unloading, import clearance, duties and inland delivery are on your side. CIF only requires minimum insurance (Institute Cargo Clauses C) for 110% of the contract value, so ask for Clauses A if you want all-risks cover.
What to send for a CIF quotation: grade (or the standard and loss class you need), thickness and width, coil ID/OD or lamination drawing, quantity per shipment, destination port, required documents, and whether you want Clauses A insurance.
Documents with every shipment
- Commercial invoice, packing list and bill of lading
- Baosteel mill certificate and our inspection report, traceable by coil number
- Insurance certificate (CIF)
- Certificate of origin and the tariff code on the invoice if your agente aduanal asks for it
