【Trade Mechanics】Back-to-Back LC Structure in Commodity Trading Explained
Quote from chief_editor on May 23, 2026, 3:30 pmBack-to-back LC structure in commodity trading explained. Understand how intermediary traders use two linked LCs to finance deals without own capital.
A back-to-back Letter of Credit (LC) is a financing structure in which an intermediary trader uses a Letter of Credit received from their buyer as collateral to open a second, separate Letter of Credit in favor of their supplier. The two LCs are legally independent — banks do not link them contractually — but they are operationally synchronized so that the intermediary can pay the supplier using funds received from the buyer's bank. This structure allows a trading company to complete a commodity transaction without committing its own capital to pay the supplier upfront.
The reason back-to-back LCs are used is that intermediary traders often lack the working capital to pay a supplier before collecting from a buyer. The structure converts the buyer's credit strength into a payment instrument the supplier will accept.
How a Back-to-Back LC Transaction Works
The process involves two separate LCs that mirror each other in terms of commodity, quantity, and shipment period, but differ in price and — critically — expiry date. First, the buyer opens a Master LC (also called the Parent LC) in favor of the intermediary trader. This LC states the full contract price and gives the intermediary a defined period to present shipping documents.
The intermediary then takes this Master LC to their own bank and uses it as security to open a second LC — the Back-to-Back LC — in favor of the upstream supplier. This second LC is issued at the supplier's price, which is lower than the buyer's price. The difference between the two prices is the intermediary's gross margin. The Back-to-Back LC typically has an expiry date a few days earlier than the Master LC, giving the intermediary time to substitute their own invoice and documents before presenting to the buyer's bank.
For example, assume a trading company in Dubai buys 10,000 metric tons of sugar from a Brazilian producer at assume $320 per metric ton and sells it to an Egyptian buyer at assume $330 per metric ton. The Egyptian buyer opens a Master LC for $3.3 million. The Dubai trader takes this LC to their bank and opens a Back-to-Back LC for $3.2 million in favor of the Brazilian producer. The Brazilian producer ships the cargo, presents documents under the Back-to-Back LC, and receives $3.2 million. The Dubai trader substitutes the supplier's invoice with their own invoice for $3.3 million, presents the full document set under the Master LC, and receives $3.3 million. The $100,000 difference represents the gross margin before financing and bank charges.
Risks and Limitations of the Structure
Back-to-back LCs carry operational risk at the document substitution stage. If the intermediary cannot substitute invoices and documents correctly before the Master LC expiry, the entire payment chain may break down. Banks typically assist with this substitution process, but the timing window is tight and must be planned carefully.
Banks treat back-to-back LCs as a credit exposure, not simply a documentary service. The issuing bank of the Back-to-Back LC takes on an obligation to pay the supplier regardless of whether the buyer's bank honors the Master LC. If the Master LC is not paid — for example due to document discrepancies — the intermediary's bank still owes the supplier. This is why banks require the intermediary to have a credit facility large enough to cover the Back-to-Back LC independently.
Transferable LCs are an alternative structure that involves a single LC that the intermediary can transfer in whole or in part to the supplier. A Transferable LC is explicitly marked as transferable on its face and transfers the buyer's bank obligation directly to the supplier. Unlike back-to-back LCs, transferable LCs do not create a second independent bank obligation — but they do require the buyer's explicit agreement to a transferable structure, which not all buyers accept.
A back-to-back LC allows an intermediary trader to participate in a commodity deal by using the buyer's creditworthiness as a financing bridge — the core mechanics depend on precise document timing and bank cooperation at each stage of the chain.
Back-to-back LC structure in commodity trading explained. Understand how intermediary traders use two linked LCs to finance deals without own capital.
A back-to-back Letter of Credit (LC) is a financing structure in which an intermediary trader uses a Letter of Credit received from their buyer as collateral to open a second, separate Letter of Credit in favor of their supplier. The two LCs are legally independent — banks do not link them contractually — but they are operationally synchronized so that the intermediary can pay the supplier using funds received from the buyer's bank. This structure allows a trading company to complete a commodity transaction without committing its own capital to pay the supplier upfront.
The reason back-to-back LCs are used is that intermediary traders often lack the working capital to pay a supplier before collecting from a buyer. The structure converts the buyer's credit strength into a payment instrument the supplier will accept.
How a Back-to-Back LC Transaction Works
The process involves two separate LCs that mirror each other in terms of commodity, quantity, and shipment period, but differ in price and — critically — expiry date. First, the buyer opens a Master LC (also called the Parent LC) in favor of the intermediary trader. This LC states the full contract price and gives the intermediary a defined period to present shipping documents.
The intermediary then takes this Master LC to their own bank and uses it as security to open a second LC — the Back-to-Back LC — in favor of the upstream supplier. This second LC is issued at the supplier's price, which is lower than the buyer's price. The difference between the two prices is the intermediary's gross margin. The Back-to-Back LC typically has an expiry date a few days earlier than the Master LC, giving the intermediary time to substitute their own invoice and documents before presenting to the buyer's bank.
For example, assume a trading company in Dubai buys 10,000 metric tons of sugar from a Brazilian producer at assume $320 per metric ton and sells it to an Egyptian buyer at assume $330 per metric ton. The Egyptian buyer opens a Master LC for $3.3 million. The Dubai trader takes this LC to their bank and opens a Back-to-Back LC for $3.2 million in favor of the Brazilian producer. The Brazilian producer ships the cargo, presents documents under the Back-to-Back LC, and receives $3.2 million. The Dubai trader substitutes the supplier's invoice with their own invoice for $3.3 million, presents the full document set under the Master LC, and receives $3.3 million. The $100,000 difference represents the gross margin before financing and bank charges.
Risks and Limitations of the Structure
Back-to-back LCs carry operational risk at the document substitution stage. If the intermediary cannot substitute invoices and documents correctly before the Master LC expiry, the entire payment chain may break down. Banks typically assist with this substitution process, but the timing window is tight and must be planned carefully.
Banks treat back-to-back LCs as a credit exposure, not simply a documentary service. The issuing bank of the Back-to-Back LC takes on an obligation to pay the supplier regardless of whether the buyer's bank honors the Master LC. If the Master LC is not paid — for example due to document discrepancies — the intermediary's bank still owes the supplier. This is why banks require the intermediary to have a credit facility large enough to cover the Back-to-Back LC independently.
Transferable LCs are an alternative structure that involves a single LC that the intermediary can transfer in whole or in part to the supplier. A Transferable LC is explicitly marked as transferable on its face and transfers the buyer's bank obligation directly to the supplier. Unlike back-to-back LCs, transferable LCs do not create a second independent bank obligation — but they do require the buyer's explicit agreement to a transferable structure, which not all buyers accept.
A back-to-back LC allows an intermediary trader to participate in a commodity deal by using the buyer's creditworthiness as a financing bridge — the core mechanics depend on precise document timing and bank cooperation at each stage of the chain.