I once watched a five-figure shipment sit in a bonded warehouse for the better part of three weeks because a packing list read "cartons" where the credit said "boxes." One word. That is the world of the documentary letter of credit, and it rewards precision far more than it rewards goodwill. A letter of credit swaps a buyer's promise to pay for a bank's promise to pay, so the exporter collects when the paperwork matches the terms, not when the buyer eventually feels like releasing funds. We at GetTransport.com don't issue credits. We're a freight marketplace connecting shippers with carriers, not a bank or a customs broker. But we move the cargo those credits ride on, and over the years we've seen exactly where they work beautifully and where they quietly fall apart.
What a documentary letter of credit actually is
Picture two companies on opposite sides of the planet who have never met. The seller in Vietnam doesn't want to ship goods and hope a buyer in Chile pays. The buyer in Chile doesn't want to wire money and hope goods arrive. Neither side trusts the other, and courts across borders are slow and expensive. A letter of credit, also called a documentary credit or simply an LC, resolves that standoff by inserting a bank in the middle.
The issuing bank, acting for the buyer, makes a written commitment: it will pay the seller a stated amount once the seller presents documents that comply with the credit's terms. The key phrase in the rulebook is "complying presentation." Payment turns on documents, not on the physical goods. This is the autonomy principle, and it runs deep. Under the International Chamber of Commerce rules, banks deal with paper, not with the cargo itself or the underlying sales contract. If the documents look right on their face, the bank pays.
That single idea explains almost everything else about how these instruments behave. It is also why a "boxes" versus "cartons" mismatch can freeze payment on goods that shipped perfectly.
Who's who: the parties to a credit
Trade finance has its own cast of characters, and mixing them up causes real confusion when things go sideways. Here is who does what.
- Applicant: the buyer (importer) who asks its bank to open the credit.
- Beneficiary: the seller (exporter) who gets paid against documents.
- Issuing bank: the buyer's bank, which carries the actual payment obligation.
- Advising bank: usually in the seller's country; it authenticates the credit and passes it on. It takes on no payment liability by merely advising.
- Confirming bank: a bank (often the advising bank) that adds its own separate guarantee to pay, layering its credit standing on top of the issuing bank's.
- Nominated bank: the bank authorised in the credit to pay against complying documents or to negotiate them.
UCP 600 Article 2 defines each of these roles precisely, which matters because a beneficiary's rights against an advising bank differ enormously from its rights against a confirming bank. If you're the exporter and you want a bank in your own country legally on the hook, you want confirmation, not just advising.
The process, step by step
Here is how a typical sight credit runs from handshake to payment. The sequence rarely changes, though the timing does.
- 1. Sales contract. Buyer and seller agree price, goods, Incoterms rule, and that payment will be by irrevocable LC.
- 2. Application and issuance. The buyer applies to its bank, which issues the credit. Across the SWIFT network this typically travels as an MT700 message, the standard format for a commercial documentary credit.
- 3. Advising. The credit reaches a bank near the seller, which advises it. Where a second advising bank is needed, banks use an MT710 rather than the original MT700.
- 4. Shipment. The seller ships the goods and collects the transport document from the carrier.
- 5. Presentation. The seller assembles the exact documents the credit demands and presents them, usually to the nominated or confirming bank, before the expiry and presentation deadlines.
- 6. Examination. The bank checks the documents against the credit. If they comply, it pays or promises to pay.
- 7. Reimbursement. Documents move up the chain to the issuing bank, which pays the presenting bank and hands the documents to the buyer so it can clear and collect the cargo.
Under UCP 600 Article 14, each bank in that chain gets a maximum of five banking days after presentation to decide whether the documents comply. Miss the deadline to raise a refusal, and Article 16(f) is brutal: the bank is precluded from claiming the documents were discrepant. It must pay.
Types of letter of credit
People say "letter of credit" as if it were one thing. It isn't. The label stacks several independent choices, and each choice moves risk and cost. Timing is one axis. A sight credit pays on presentation of complying documents. A usance or deferred credit pays a set number of days later, say 90 days after the bill of lading date, which is effectively the seller financing the buyer.
Whether a second bank guarantees payment is another axis entirely. Below is how the main variants compare.
| Type | What it does | Typically used when |
|---|---|---|
| Irrevocable | Cannot be changed or cancelled without every party's consent. The default under UCP 600. | Almost all modern trade credits. |
| Confirmed | A second bank adds its own payment guarantee alongside the issuing bank. | Issuing bank or country risk worries the exporter. |
| Sight | Pays on presentation of complying documents. | Seller wants fast payment. |
| Usance / deferred | Pays at a future date after presentation or shipment. | Buyer negotiates credit terms. |
| Standby (SBLC) | A backstop paid only if the buyer defaults; closer to a guarantee. | Recurring supply, performance security. |
| Transferable | Lets the first beneficiary transfer part or all to a second beneficiary. | Middlemen and trading houses. |
| Revolving | Reinstates automatically for repeated shipments. | Ongoing contracts, regular deliveries. |
| Back-to-back | Two separate credits, the export one opened on the strength of the import one. | Intermediary lacks its own bank line. |
| Red clause | Lets the seller draw an advance before shipping. | Seller needs pre-shipment finance. |
A quick word on the standby. An SBLC behaves less like a payment mechanism and more like a safety net, since it only pays out if the primary obligation fails. On the SWIFT network, standbys and demand guarantees moved to the MT760 format after the SR 2020 standards release, separating them cleanly from commercial credits. In our experience, standbys show up a lot in long-running carrier and vendor relationships where nobody wants to re-paper a fresh credit for every load.
The documents, and how the LC ties to Incoterms
An LC is only as good as the documents it names. Get the document list wrong at contract stage and you inherit a payment problem later. The usual suspects:
- Commercial invoice: governed by UCP 600 Article 18. It must be issued by the beneficiary, made out to the applicant, and describe the goods in wording that corresponds to the credit.
- Transport document: most often an ocean bill of lading, addressed by Article 20. An on board notation and the shipment date matter enormously here.
- Insurance document: under Article 28, cover must be for at least 110% of the CIF or CIP value of the goods.
- Certificate of origin: proof of where the goods were made, which also drives duty treatment. Our certificate of origin guide walks through preferential versus non-preferential.
- Packing list: carton counts and weights that had better match everything else on the presentation.
The chosen Incoterms rule quietly dictates parts of that list. Sell on CIF or CIP and you, the seller, must arrange and prove insurance, so the credit will demand an insurance document. Note that the 2020 revision lifted the required cover for CIP up to all-risks Institute Cargo Clauses (A) while CIF stayed at the more basic clauses. Choosing between duty-paid and duty-unpaid terms shifts the customs burden too, which we unpack in our piece on DDP versus DAP and who pays the tariff. And because certificates of origin and duty claims hinge on classification, getting the tariff code right is upstream of all of it; here's how to find and verify an HS code.
The rulebook: UCP 600, ISBP 821, eUCP and URDG
Letters of credit run on privately written rules that banks agree to follow, not on a single global statute. The backbone is the ICC's Uniform Customs and Practice for Documentary Credits, publication 600, universally shortened to UCP 600. The ICC Banking Commission approved it on 25 October 2006 by a unanimous 91 to 0 vote, and it came into force on 1 July 2007, replacing UCP 500. Its 39 articles are what your credit incorporates when it states "subject to UCP 600."
Around that core sit companion texts. ISBP 821, the current International Standard Banking Practice published by the ICC in 2023 to replace the 2013 edition ISBP 745, tells document checkers how UCP principles play out line by line on invoices, transport documents and the rest. For electronic and part-electronic presentation, the eUCP applies; its current Version 2.1 took effect on 1 July 2019. And when the instrument is a demand guarantee rather than a credit, the relevant rulebook is the ICC's URDG 758, a set of 35 articles in force since 1 July 2010. A newer wave of ISO 20022 messages for guarantees and standbys has been approved, though adoption is expected to spread gradually over several years rather than flip overnight.
On the stability of all this, the signal from the ICC in 2026 is continuity rather than upheaval. At the ICC Banking Commission meeting in Paris in March 2026, twenty national committees voted against revising UCP 600 or ISBP 821, and the 2026-2027 action plan puts the emphasis on education and interpretive guidance instead of a rewrite. The live frontier is hybrid presentation, where paper and electronic documents arrive together, and that is exactly where document checkers are asking for clearer direction. It is one more reason to agree the exact presentation format with your bank before the first drawing.
Discrepancies, cost, and when an LC is worth it
Now the part that trips up first-time exporters. Discrepancies are shockingly common. Industry surveys have long put the rate of documents rejected on first presentation above half; the widely cited DC-PRO LC Market Intelligence Survey recorded 56%, and various ICC-referenced estimates push the range toward 60 to 80%. In plainer terms, most presentations get bounced the first time. A rejected presentation doesn't usually kill the deal, but it delays payment and can rack up fees.
We've had exporters who assumed the bank would "understand what they meant." It won't. The examiner compares strings of text. A description that reads slightly differently from the credit, a transport document without the on board notation, an expired presentation window, a missing signature the credit required. Any one of these is a discrepancy. The defence is boring and effective: build the exact document list into the contract, read the credit the day it arrives, and fix wording before you ship, not after.
Cost matters too. An LC carries issuance and advising fees, plus a confirmation fee if you ask for it, and those charges climb with the perceived risk of the issuing bank and its country. Against that, weigh the alternatives. Open account is cheapest and buyer-friendly but leaves the seller exposed. Cash in advance flips the exposure entirely onto the buyer. Documentary collection sits in between and costs less than an LC, yet it gives no bank payment guarantee. An LC earns its fees when the counterparty is new, the sum is large, or the country risk is real. For a trusted repeat buyer on modest volumes, it's often overkill. One related structure worth knowing is the on board bill of lading paired with FCA terms, which we cover in our guide to FCA Incoterms 2020, the on board bill of lading and the letter of credit.
Frequently asked questions
Is a letter of credit the same as a bank guarantee?
No, though they're cousins. A commercial LC is a primary payment mechanism: the bank pays the seller when complying documents arrive. A guarantee, and its close relative the standby LC, pays only if something goes wrong, such as the buyer defaulting. Guarantees follow the ICC's URDG 758 rather than UCP 600, and on SWIFT they travel as MT760 messages.
Are letters of credit still irrevocable by default in 2026?
Yes. Under UCP 600 an LC is irrevocable unless it clearly says otherwise. Article 2 defines a credit as an irrevocable undertaking, and Article 3 confirms it is irrevocable even where the credit gives no indication to that effect. Revocable credits, common decades ago, have effectively vanished from modern trade.
Who chooses the required documents?
The buyer specifies them in the application, but a smart seller negotiates that list into the sales contract first. That way the credit simply mirrors what both sides already agreed. When we advise shippers, this is the single highest-leverage step. Fix the document list early and you head off most discrepancies before they exist.
How long does the bank have to examine documents?
A maximum of five banking days following the day of presentation, per UCP 600 Article 14. If a bank wants to refuse for discrepancies, it must send a single notice within that window. Blow the deadline and Article 16(f) strips its right to object, so it has to pay.
Can I present documents electronically?
Increasingly, yes, where the credit is issued subject to the eUCP. Version 2.1, effective since 1 July 2019, sets out how electronic records may be presented alone or alongside paper. Uptake varies by bank and by trade lane, and plenty of credits still run on paper, so confirm the format with your bank before you rely on it.