Cross-border (Mexico) waybills

Mexican law (SAT Carta Porte) requires customs and tariff data on top of a standard bill of lading whenever a shipment crosses the US–Mexico border. Cedar enforces these rules during 824 application advice validation against every waybill created or updated through /ims/waybills/bill-of-lading (and every equivalent inbound EDI message). Missing or malformed data surfaces as an 816* or 825* error code on the resulting waybill.

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When the requirements apply

The Carta Porte data block is required when both of the following are true:

• shipmentQualifier is one of 6 (split first bill), 7 (split subordinate), B (single BOL), C (consolidated), F (stop-off), M (master BOL), S (submaster BOL), W (revenue empty).
• Exactly one of originStation and destinationStation resolves to Mexico (origin xor destination — pure intra-Mexico moves are currently not validated by this rule). Cedar resolves the country from countryCode if present, otherwise from stateOrProvince.

Empty, intermodal, switch, blind-memo, and company-business qualifiers (1, 8, E, G, H, I, N, X) are exempt regardless of route.

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Where the data goes

Carta Porte data is attached to the equipment, not to the top-level lineItems[] array: The two arrays are not interchangeable. waybill.lineItems[].quantity is a nested LineItemQuantity object (billedAsQuantity, weightQualifier, etc.); shipmentInfo[].lineItems[].quantity is a flat numeric field corresponding to the X12 417 N1001 element. A cross-border waybill needs both populated. When waybillTemplateId is set on a /ims/waybills/bill-of-lading request, Cedar merges template data with the request rather than replacing the waybill wholesale.

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equipmentDetails[].shipmentInfo[]

• When the request includes commodityCode or commodityDescription on a shipmentInfo line item, that block is taken from the request as-is (template values for that block are not merged in).
• Otherwise, template Carta Porte scaffolding (for example referenceIdQualifier, referenceId, extendedReferenceInfo, and commodity codes on line items) is deep-merged with the request. Request non-null fields such as quantity, weight, and weightUnitCode override the template at the field level.
• Omitted or null request fields do not clear template data.
• When the request includes a non-null shipmentInfo[].lineItems[].weight, that value is also written to the lead equipment’s netWeightLbs and grossWeightLbs (converted to pounds when weightUnitCode is K).

You can send minimal request shipmentInfo containing only dynamic line-item fields (quantity, weight, weightUnitCode) and rely on the template for Carta Porte reference data and commodity codes.

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parties[]

• Shipper, consignee, freight bill party, and in-care-of (one per bill): if the request party includes any body field (name, address, city, and so on), the request owns the entire party body. Otherwise Cedar uses the template party body. administrativeContacts, billingInfo, and referenceInfo from the request and template are all retained — for example, a request shipper address plus template Carta Porte contacts.
• All other party types (for example Rule 11): every party from the request and every party from the template is kept.

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Required content of each shipmentInfo[] entry

For each commodity on each piece of equipment:

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Hazardous shipments

If the waybill has any hazardousInfo[] entries, every shipmentInfo[] block with referenceIdQualifier = UNC must additionally include at least one extendedReferenceInfo[] entry with referenceIdQualifier = MHC (Mexico SAT Hazardous Code). The MHC value must be prefixed with UN and must exist in the Carta Porte reference data.

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Required shipper contact

Cross-border waybills must include a parties[] entry with partyType = SH (shipper) that has at least one administrativeContacts[] entry containing all of:

• contactFunctionCode = SP
• a non-empty name
• communicationNumbers[] with the first entry qualifier = TE (telephone) and a non-empty number, and the second entry qualifier = EM (email) and a non-empty number