Shipper Letter of Instruction
A shipper letter of instruction, usually shortened to SLI, is the exporter’s instruction sheet to the freight forwarder or other authorized agent handling an export shipment. It gives the forwarder the shipment details needed to move the cargo, but its real value is compliance: the SLI tells the forwarder who the parties are, what is being exported, how it should be classified, whether Electronic Export Information (EEI) must be filed in the Automated Export System (AES), and what authority the forwarder has to act on the exporter’s behalf.
A Shipper Letter of Instruction (SLI) is a document provided by the exporter to the freight forwarder authorizing them to handle the shipment and containing the export information needed to book cargo, file EEI when required, and support compliance.
What is a Shipper Letter of Instruction (SLI)?
An SLI is not a single government-issued form with one universal layout. It is a practical export document, usually created by the exporter or provided as a template by the freight forwarder, that captures the shipment information and authorization needed to move an international shipment and handle export filing correctly.
The legal significance comes from what the document supports. Current U.S. Census guidance says that if a U.S. Principal Party in Interest (USPPI) delegates EEI filing to an authorized agent, the USPPI must provide a properly executed power of attorney or written authorization. An SLI is commonly used to capture that authorization together with the shipment data the agent needs to file accurately.
When is an SLI required?
The better question is usually not whether a document titled “SLI” is legally required for every export, but whether the shipment requires written instructions and authorization for the forwarder to act. Many exporters use an SLI on every forwarder-managed export because it standardizes the information flow, even when EEI is not required.
- Use an SLI when a freight forwarder or other U.S. authorized agent will file EEI in AES for the exporter.
- Use an SLI when the shipment is a routed export transaction and multiple parties are sharing filing responsibilities.
- Use an SLI when the shipment contains licensed goods, controlled items, or destination/end-user concerns that require clear instructions.
- Use an SLI when your forwarder, carrier, or internal export procedure requires one even for shipments that move under a NO EEI legend.
EEI itself is generally required when the value exceeds $2,500 per Schedule B number, when the shipment requires a license, or when another filing rule applies. Important exclusions and exemptions still exist, including many shipments to Canada, low-value shipments that qualify for NO EEI 30.37(a), and intangible electronic transmissions. Even then, companies often still issue an SLI so the forwarder has the right booking instructions and exemption legend.
Required fields on an SLI
There is no single mandated SLI layout, but a strong SLI should collect the information the forwarder needs to move the cargo and, where applicable, prepare an accurate EEI filing.
Shipper or exporter information
Start with the USPPI details exactly as they should appear in the export record.
- USPPI legal name and address
- EIN, DUNS, or other applicable identifier
- Contact name, email, and phone number
- Forwarding agent name and contact details if already assigned
Consignee and notify party
The SLI should distinguish between the ultimate consignee, any intermediate consignee, and the notify party if one is used.
- Ultimate consignee name and address
- Intermediate consignee, buyer, or distributor if applicable
- Notify party details
- Country of ultimate destination
Commodity description and Schedule B or HTS code
This is one of the highest-risk sections. Generic descriptions like “parts,” “samples,” or “FAK” are not enough.
- Commercial description detailed enough to support classification
- Schedule B number or permitted HTS code
- ECCN if applicable, or internal classification notes
- Domestic or foreign origin indicator
Value, weight, and package count
The SLI should give the forwarder the commercial facts needed for filing, carrier booking, and downstream customs paperwork.
- Unit price and total shipment value in U.S. dollars
- Package count and packaging type
- Net quantity and unit of measure for each line item
- Gross shipping weight in kilograms or pounds, depending on internal workflow
AES and ITN information
If EEI will be filed, the SLI should make the filing expectation explicit. If EEI is not required, it should tell the forwarder what NO EEI legend applies.
- Indication of whether the USPPI or forwarder is filing EEI
- Requested filing timing and shipment reference number
- License code, license number, or NLR/NO EEI legend as applicable
- Space to return or record the Internal Transaction Number (ITN)
Routing instructions
An SLI is still an operations document. It should tell the forwarder how the shipper wants the cargo handled from pickup through export.
- Requested mode of transport and service level
- Port of export, port of unloading, and destination if known
- Booking number, carrier preference, or carrier restrictions
- Incoterms, pickup instructions, and requested ship date
Special handling instructions
This section captures anything that could affect safe handling, customs processing, or compliance review.
- Hazardous materials status and supporting documents
- Temperature control or product sensitivity
- Screening notes, end-use concerns, or destination restrictions
- Document distribution requirements for the exporter, consignee, or bank
Power of attorney or authorization
When a forwarder is filing EEI on behalf of the exporter, the SLI often includes certification language, signature blocks, and a statement authorizing the forwarder to prepare and transmit the required data. Some companies keep the power of attorney as a separate standing document and use the SLI to reference it.
- Exporter certification that the data provided is true and complete
- Written authorization for the forwarder to file or arrange export documentation
- Signature, name, title, and date
- Reference to any separate power of attorney already on file
SLI vs other export documents
Export teams often mix up the SLI with other documents because the same shipment data appears in several places. The difference is purpose: the SLI instructs and authorizes, while the other forms support billing, packing visibility, or carriage.
SLI vs commercial invoice
The commercial invoice is the seller’s billing document. It shows what was sold, to whom, and for how much. The SLI, by contrast, is an instruction document sent to the forwarder. An invoice may support customs valuation and payment terms, but it does not by itself tell the forwarder who should file EEI or whether the forwarder has written authorization to act.
SLI vs packing list
The packing list explains how the cargo is physically packed: carton counts, dimensions, weights, and marks. The SLI may repeat some package data, but it adds compliance and routing instructions that the packing list usually does not contain.
SLI vs shipping instructions (SI)
Shipping instructions are typically the instructions provided to a carrier or NVOCC for issuing the bill of lading. They focus on transport details, bill of lading parties, cargo descriptions, and release instructions. An SLI is broader from the exporter’s side because it includes filing, compliance, and authorization data.
SLI vs bill of lading
The bill of lading is the carriage document issued by the carrier or NVOCC. The SLI is upstream from the bill of lading: it tells the forwarder how to prepare the shipment and what instructions to pass to the carrier, but it is not itself the transport contract.
SLI and export compliance
A well-prepared SLI reduces compliance risk because it gathers the facts that determine whether EEI is required, whether a license or license exception is involved, and whether the shipment details make sense before cargo moves.
Current Census guidance says the USPPI must provide a properly executed power of attorney or written authorization when delegating EEI filing to an authorized agent, and all parties to the export transaction must retain export documents for five years from the date of export. BIS guidance separately emphasizes classification, end-use and end-user review, and screening restricted parties through the Consolidated Screening List.
- AES filing: the SLI gives the forwarder the data elements needed to prepare an accurate EEI filing or annotate a shipment with the correct NO EEI legend.
- Denied party screening: the SLI surfaces consignee, intermediate consignee, and destination information early enough for screening before export.
- License review: the SLI is where exporters often communicate ECCN, EAR99 status, license numbers, or special destination restrictions.
- Audit defense: if Customs, Census, or BIS questions the shipment later, the SLI helps show what instructions and data were provided at time of export.
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SLI template and example
There is no single official U.S. government SLI template that every exporter must use. A useful template should be easy for operations teams to complete and detailed enough for the forwarder to file correctly.
Sample SLI layout
- Exporter section: USPPI name, address, EIN, contact, and date.
- Forwarder section: authorized agent name, office, and file reference number.
- Parties section: ultimate consignee, intermediate consignee if any, notify party, and destination country.
- Commodity section: line-item description, Schedule B or HTS number, ECCN if applicable, quantity, and value.
- Transportation section: mode, requested ship date, port of export, destination, booking number, and Incoterms.
- Compliance section: EEI required yes or no, filing party, NO EEI citation or license code, and space for the ITN.
- Handling section: hazardous status, temperature or handling notes, document distribution, and special instructions.
- Authorization section: certification statement, signature, printed name, title, and date.
Field-by-field walkthrough
If you are building or reviewing an SLI template, focus first on the fields that commonly create filing errors. Make sure party names match the commercial documents, use a real commodity description instead of shorthand, confirm the Schedule B number with someone accountable for classification, and state clearly whether EEI will be filed or a NO EEI citation applies.
Common mistakes to avoid
- Treating the SLI as optional and sending only an invoice and packing list.
- Using vague commodity descriptions that do not support the reported Schedule B classification.
- Leaving the authorization language blank when the forwarder is expected to file EEI.
- Failing to state the correct NO EEI citation for low-value or otherwise exempt shipments.
- Assuming the SLI replaces screening, license review, or recordkeeping controls.
- Not keeping the signed SLI and supporting emails with the rest of the shipment record.
SLI FAQs
What is a shipper letter of instruction?
It is the exporter’s instruction and authorization document for the freight forwarder or authorized agent handling an export shipment.
What information is required on an SLI?
At minimum, an effective SLI should identify the exporter, consignee, destination, commodity description, Schedule B or HTS number, value, quantity, routing instructions, filing direction, and authorization for the forwarder to act.
Is an SLI required for all exports?
No. Not every export legally requires a document titled SLI. But when a forwarder is filing EEI for the exporter, a written authorization or power of attorney is required, and many companies use the SLI to capture it.
What is the difference between SLI and SI?
An SLI is the exporter’s instruction to the forwarder. Shipping instructions, or SI, are usually the carrier-facing instructions used to issue the bill of lading.
Who prepares the SLI?
The exporter or USPPI normally prepares or approves the SLI, often using a freight forwarder template. The exporter remains responsible for the accuracy of the shipment data it provides.
How long must you keep SLI records?
For U.S. export transactions, Census guidance says export documents must be retained for five years from the date of export. If another agency with jurisdiction over the goods imposes a longer retention period, that longer period controls.
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Related glossary terms
AES Filing
What is AES filing? Learn Automated Export System requirements, exemptions, ITN numbers, filing deadlines, and penalties for non-compliance.
Shipping Instructions
Learn what shipping instructions (SI) are, how export shipping instructions work, and why accurate SI data matters after booking confirmation.
AES Filing
What is AES filing? Learn Automated Export System requirements, exemptions, ITN numbers, filing deadlines, and penalties for non-compliance.
