> ## Documentation Index
> Fetch the complete documentation index at: https://docs.jaantonio.com/llms.txt
> Use this file to discover all available pages before exploring further.

# Exchange-difference lines

> Why CargoWise EXX match lines are excluded from stamped payment complements.

CargoWise can post exchange-difference (EXX) match lines on a payment receipt. Those lines are accounting adjustments for FX differences. They are **not** payment allocations that belong on a SAT complemento de pago.

Lambda excludes EXX lines from the stamped REP.

## What that means

* The payment CFDI covers the real PPD payment allocations that remain after EXX lines are removed.
* EXX amounts stay in CargoWise accounting; they do not become REP match lines.
* Omitting EXX is expected behavior, not a missing-line failure.

If the receipt also has ordinary PPD allocations, those still reconcile and stamp under the normal [payment complement](/stamping/payment-complements) rules.

## What it is not

* Not an FX inventing rule — cross-currency payments still need proven rate or MXN evidence for the lines that do stamp. See [Troubleshooting](/troubleshooting#fx-evidence-missing).
* Not the same as the [REP eligibility window](/stamping/special/rep-eligibility-window), which decides parent inclusion by PostDate days.

## Related

* [Payment complements](/stamping/payment-complements)
* [Rules](/stamping/rules)
* [Special behaviors](/stamping/special/overview)