Skip to content

ISO 20022 Academy

ISO 20022 Academy

ISO 20022 element

<Undrlyg>

Underlying — which payment a cancellation/investigation refers to.

Cardinality (typical): 1..1

ISO 20022 Academy

The best place on the internet to understand, explore, and experiment with ISO 20022.

This started as my own study notes — one person trying to make sense of a standard everyone said to “just read the spec” for. It grew into the resource I wish someone had handed me on day one. If it helps you, that's the entire reward. — Revanth Sai Rayapati

Explore History Library Playground Workshop Glossary Dictionary What's new

Stay in the loop

New lessons, now and then.

Get an email when a new lesson or tool lands. No spam, unsubscribe anytime.

ISO 20022 Academy · An interactive academy for how money moves · © 2026