SPEI vs ACH: Cross-Border Payment Methods Compared

SPEI (Sistema de Pagos Electrónicos Interbancarios) is Mexico’s real-time gross settlement system operated by Banco de México. SPEI transfers settle in seconds and operate Monday-Friday 7am-5:30pm CT. Each bank sets its own SPEI fee, and receiving a transfer is free. SPEI is the backbone of B2B payments in Mexico’s fuel industry.

ACH (Automated Clearing House) is the US batch payment system. Standard ACH settles in 1-2 business days, same-day ACH settles by end of day, and FedNow (24/7/365 instant) is the newest option. Each bank charges its own fee to send or receive an ACH or wire payment.

For US-Mexico fuel trade, the optimal strategy depends on urgency and volume: (1) Standard operations: SPEI for MXN + ACH credit or wire for USD, paid straight into the seller’s verified account, (2) Urgent payments: FedNow or RTP (USD side) + SPEI (MXN side), where both banks support them, (3) High-volume: a forward contract with your own bank or FX provider to fix the exchange rate for 30/60/90 days.

Cantarell OS never holds or moves your money. It gives the buyer payment instructions for the seller’s verified account (SPEI, ACH credit, wire or FedNow), matches each payment to its order by its unique reference, and verifies Mexican payments against Banxico’s electronic payment receipt (CEP).