How does a SPEI payment work?
For a pay-in, the provider assigns the shopper a CLABE, either a unique reference account per customer or per order, and shows it at checkout with the exact amount. The shopper opens their banking app, creates a SPEI transfer to that CLABE and confirms it. Banco de México’s system settles the transfer between the two banks in real time, and the receiving provider matches the incoming funds to the order by CLABE and reference and notifies the merchant. The recipient can download an electronic proof of payment, the CEP, from Banco de México once funds are credited. For a pay-out, the provider sends a SPEI transfer to the customer’s CLABE and the money usually arrives within seconds, day or night, including weekends and public holidays. Because each transfer carries the sender’s account details, the merchant also receives information about who paid, which supports reconciliation and checks that the payer is the account holder on file.
Why does SPEI matter for merchants?
SPEI is the backbone of digital money movement in Mexico. Every credit institution participates. The system processed 3,894 million transfers in 2023, and Banco de México’s governor told the 2026 banking convention that it handled more than 7.3 billion transfers in 2025, worth close to MXN 600 trillion, or 16.8 times that year’s GDP, as reported by La Razón. Xataka México, citing Banxico figures via STP, put the growth in the number of transfers at 36.8% on 2024. Expansión reported in August 2026 that 73.5 million adults use SPEI and that Banxico expects SPEI operations to outnumber card payments by the end of 2026. Banxico has also announced reforms and technical guides so that banks make transfers simpler to start from a phone. Many online shoppers in Mexico do not have a card or prefer not to use one online, so a bank transfer from an account they already use widens reach at checkout. For merchants it brings low cost per transaction, final settlement and no chargebacks. For marketplaces, SPEI is also the standard pay-out rail: seller payouts reach a Mexican bank account in seconds, which is what sellers expect.
What can go wrong?
SPEI problems are mostly about matching. Shoppers send the wrong amount, type the CLABE incorrectly, or reuse an old reference, so the provider receives money it cannot match to an open order. Stripe, for example, holds Mexican bank transfers in a customer balance so overpayments and underpayments can be reconciled, and tries to return funds that stay unreconciled for more than 75 days. Some banks apply daily transfer limits or extra authentication for new beneficiaries, which slows the first payment to a merchant. Because the shopper has to leave the checkout and come back, abandonment is higher than with in-page methods. On pay-outs, a wrong CLABE or a name mismatch causes a return, and returned transfers have to be reconciled and resent. Third-party payments, where someone else pays for the customer, make reconciliation and fraud checks harder because the paying account does not match the customer on file.
How would Omno handle SPEI?
A merchant would show the payment instructions in the hosted checkout or take them through Direct Links on its own checkout, with a reference CLABE from the provider tied to the customer or order. Incoming transfers would be matched and the final status would reach the merchant by webhook, which is the source of truth for confirming the order. Customer groups and customer verification levels, passed from the merchant’s own verification provider, could require that the paying account is in the customer’s own name. Routing rules set by the merchant would choose the provider for pay-ins and pay-outs. For pay-ins in the hosted checkout and for pay-outs, if a provider is unavailable or rejects a request, it moves to the next provider in the rule until one accepts. The routing-decision log would show which provider handled each payment.