More Incoterms & Transport Documents
Shipper's Letter of Instruction
Also known as: SLI
A shipper's letter of instruction is a document in which an exporter conveys detailed shipping and documentation instructions to its freight forwarder, authorizing the forwarder to act on its behalf and specifying how the shipment should be routed, documented, and declared for export. It typically includes the parties, product and value details, routing preferences, and the data needed to prepare transport documents and file export declarations. By setting out the exporter's requirements clearly, the letter reduces errors, establishes the scope of the forwarder's authority, and creates a record of the exporter's instructions for the transaction.
Your written instruction to the forwarder, and the document that decides who is blamed when something is filed wrongly. Vague instructions produce filings someone else guessed at, in your name.
Where it matters for compliance
- Authorizing a forwarder to file export data does not transfer responsibility for its accuracy.
Related terms
Reviewed by a licensed customs broker. Definitions are general information, not legal or customs advice for a particular shipment. Duty rates, tariff programs and agency requirements change frequently.