Mexico — CFDI 4.0

This section covers everything needed to issue and test CFDI 4.0 documents through Vertex. It's split into three guides — read them in this order:

1. Issuing Documents in Mexico — start here. How to issue each CFDI invoice type: which payload fields control each variant, plus Postman examples.
2. Test RFCs — once you have a payload built, use this to plug in a SAT sandbox test RFC (buyer/supplier) and run it end-to-end.
3. SAT Guides (CFDI 4.0 Reference) — reference material for when you need to check the underlying SAT standard: catalogs, technical standards, and raw XML examples.