Both systems require a unified item classification (GS1 / tax codes), a digital signature, and near-real-time submission of invoices.
The key difference: ETA uses a clearance model — the invoice is cleared before being issued to the customer. ZATCA's Phase 2 (integration) rolls out in revenue-based waves.
EAMS generates, signs, and submits invoices to both systems automatically, with a retry queue for outages and a complete audit log.