Proforma vs Commercial Invoice: Why Mismatched Numbers Get Your L/C Rejected

You send a Proforma Invoice quoting $50,000 for 1,000 units. Your buyer opens a Letter of Credit based on those exact numbers. Two months later, you ship 980 units at $48,500 and issue your Commercial Invoice.

The bank rejects your documents. Your shipment is on the water, but payment is stuck.

This guide explains why your Proforma Invoice is more than a quote, how it becomes your L/C terms, and what to check so your Commercial Invoice gets accepted on the first try.

Why does your Proforma Invoice become your L/C terms?

When a buyer applies to open a Letter of Credit, the bank needs to know what they're guaranteeing payment for. The source? Your Proforma Invoice.

The bank copies your Proforma details directly into the L/C's goods description section. Your Proforma number, date, product name, quantities, and unit prices all become the official L/C terms.

Later, when you submit your Commercial Invoice for payment, the bank compares it against this section. If the numbers don't match, that's a problem.

Banks don't interpret or make judgment calls. They compare documents. If your Commercial Invoice says something different from the L/C, that's a discrepancy. This is why a Proforma Invoice functions more like a contract than a quote.

How often do L/C documents get rejected?

According to the DC-Pro LC Market Intelligence Survey, the average rejection rate on first-time submissions is 56%. Other industry estimates from the ICC Banking Commission put the global rate between 60-75%.

More than half of all L/C documents fail on the first try.

The most common reasons:

• Goods description doesn't match L/C terms

• Invoice amount different from L/C amount

• Late shipment or late document submission

• Inconsistent information across documents

Under UCP 600 Article 18, your Commercial Invoice must show a goods description that matches the L/C. Not word-for-word identical, but consistent. If the L/C says "Electronic Components" and your invoice says "Electrical Parts," the bank will reject it.

What happens when the bank finds a mismatch?

When the bank spots a discrepancy, they don't pay you. Instead, they hold your documents and contact your buyer.

The bank asks: "The documents don't match the L/C terms. Do you still approve payment?"

If your buyer says yes, you get paid. If your buyer says no, you don't.

This is the problem. You've already shipped the goods. You've spent money on production, packaging, and freight. But whether you get paid now depends on your buyer's decision, not the bank's guarantee.

If the buyer refuses to approve:

• Payment denied, documents returned

• You may need to offer a discount to get approval

• Goods stuck at destination port

• Extra bank fees for resubmission

Even when buyers do approve, the process adds delays. And you've lost the security that the L/C was supposed to provide.

Where do Proforma and Commercial Invoice mismatches happen?

Most mismatches fall into four categories:

Quantity changes

Your Proforma quoted 1,000 units, but production yielded 980. Unless your L/C specifically allows a tolerance range, the bank will flag this as a mismatch.

Price adjustments

You agreed to a discount after the L/C was opened. Your Commercial Invoice shows $48,500 instead of $50,000. Even though it's less than the L/C amount, the numbers don't match. That's a discrepancy.

Description differences

Your Proforma said "Stainless Steel Bolts Grade A2-70." Your Commercial Invoice says "SS Bolts." Abbreviations or missing details can trigger rejection.

Math errors

Your Proforma shows 1,000 units × $50 = $50,000. Your Commercial Invoice shows 980 units × $50 = $49,000. Two different totals. The bank sees a mismatch.

How do you prevent rejection?

When writing your Proforma

• Only commit to quantities and prices you can deliver exactly

• Use precise product descriptions you can replicate later

• Add tolerance language if quantities may vary (e.g., "+/- 5%")

• Check with your production team before sending

After receiving the L/C

• Read it immediately

• Check that the goods description matches your Proforma

• Request an amendment if anything is wrong or impossible to meet

Before issuing your Commercial Invoice

• Compare your draft line-by-line against the L/C

• Match the product description exactly

• Verify quantity and total amount

• Make sure all other documents (packing list, B/L) show the same numbers

Proforma vs Commercial Invoice: Key differences

• Proforma Invoice: Quote sent before the sale. Buyer uses it to open the L/C. Becomes the reference standard.

• Commercial Invoice: Final bill sent after shipment. Must match L/C terms. Used for payment and customs clearance.

• Important: You cannot submit a document titled "Proforma Invoice" for payment. Banks will reject it.

• Tolerance: L/Cs may allow +/- 5% on quantity, but only if not prohibited and quantity isn't stated as exact units.

Pre-submission checklist

• Product description matches L/C exactly

• Proforma Invoice number matches L/C reference

• Quantity matches or falls within allowed tolerance

• Total amount does not exceed L/C value

• Unit price × quantity = total amount

• Currency matches L/C currency

• All documents show consistent information

• Document titled "Commercial Invoice" (not "Proforma")

Your Proforma sets the terms. Your Commercial Invoice must meet them. The gap between these two documents is where most L/C payments get stuck. Close that gap before you ship.