What is SPEI?
SPEI (Sistema de Pagos Electrónicos Interbancarios) is Mexico's interbank payment system for transfers in pesos, owned and operated by Banco de México. It settles payments in real time, 24 hours a day, 7 days a week, and gives both sides an electronic proof of payment called a CEP. Example (invented, for illustration only): a Monterrey distributor pays MX$145,000 to a supplier's CLABE 012180001234567899 by SPEI on a Saturday, and both companies download the CEP as proof.
- SPEI is owned and operated by Banco de México and moves Mexican pesos only.
- SPEI settles in real time and runs 24 hours a day, 7 days a week.
- After a transfer, the receiving bank credits the account and confirms the credit to SPEI, and either side can download the CEP, the electronic proof of payment.
- US dollar transfers between dollar accounts in Mexico use a separate system, SPID, which runs from 8:00 to 14:15 for companies domiciled in Mexico.
How SPEI works
A SPEI payment starts at the payer's bank, which sends it to Banco de México's system, identifying the payee's account by its CLABE, the 18 digit standardized account number. SPEI settles the payment between the two institutions in real time. The receiving bank then credits the account and confirms the credit to SPEI, which is what allows either party to download the CEP (Comprobante Electrónico de Pago).
Because SPEI runs every day and at every hour, a peso payment does not wait for banking hours. That makes it the rail for Mexican payroll, taxes and local suppliers.
The CEP matters as much as the transfer. Because it is downloaded from Banco de México's system once the receiving bank has confirmed the credit, a buyer and a supplier can settle a question about whether a payment arrived without relying on screenshots or emails.
| System | Currency | Hours | Who uses it |
|---|---|---|---|
| SPEI | Mexican pesos | 24 hours a day, 7 days a week | Any account with a CLABE |
| SPID | US dollars | 8:00 to 14:15 | Dollar accounts of companies domiciled in Mexico |
| SWIFT wire | USD and other currencies | Bank business days | Payments from and to banks abroad |
Sources: Banco de México, SPEI and SPID pages; BBVA México, international transfers for companies. As published on 29 October 2026.
Where a business meets SPEI
A foreign company meets SPEI when it pays a Mexican supplier in pesos. It cannot send SPEI from a US bank account; SPEI links institutions in Mexico. The two routes are a SWIFT wire to the supplier's Mexican bank, which BBVA México says takes 24 to 72 hours on average, or a provider with access to Mexican rails that converts the dollars and pays the supplier's CLABE in pesos over SPEI, so the supplier receives a domestic payment with no SWIFT receiving fee.
On the receiving side, Mexican companies that sell abroad receive dollars by SWIFT into a Mexican dollar account, and convert to pesos when they need to pay local costs over SPEI. Our guide on paying suppliers in Mexico compares the routes.
Common mistakes with SPEI
- Asking a supplier to accept dollars by SPEI. SPEI moves pesos only. Dollar transfers inside Mexico use SPID, open only to dollar accounts of companies domiciled in Mexico.
- Mistyping the CLABE. A wrong digit means a rejected or held payment. Copy it from the supplier's CFDI invoice or a signed bank letter, and check the first three digits match the supplier's bank.
- Not keeping the CEP. The CEP is the proof the supplier's accountant and your auditor will ask for. Download it for each payment.
- Changing a supplier's CLABE on an email request. Confirm any new CLABE by calling a contact you already know, on a number you already hold.
Related terms and how Helm handles it
SPEI is Mexico's counterpart to Faster Payments in the UK: real time and always open. Accounts are identified by the CLABE, not by an IBAN or a US routing number, and payments from abroad arrive first by SWIFT.
Helm pays suppliers by SWIFT and by local rails where available; your account manager confirms the route for peso payouts. The rate, fee and expected arrival are shown before you send.
Open a Helm account
USD, EUR and GBP accounts in your company's name, with a named account manager.
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What is SPEI?
SPEI, the Sistema de Pagos Electrónicos Interbancarios, is Mexico's interbank electronic payment system for transfers in pesos, owned and operated by Banco de México. It settles in real time, 24 hours a day.
Can SPEI receive US dollars?
No. SPEI moves pesos only. Dollar transfers between dollar accounts in Mexico use SPID, which runs from 8:00 to 14:15 for companies domiciled in Mexico.
What is a CEP?
The CEP, Comprobante Electrónico de Pago, is the electronic proof of a SPEI payment. Either side can download it once the receiving bank has credited the account and confirmed the credit to SPEI.
Can I send a SPEI payment from the US?
Not from a US bank account. A US company pays a Mexican supplier by SWIFT wire, or through a provider that converts the dollars and pays out in pesos over SPEI.
Does SPEI work on weekends?
Yes. SPEI runs 24 hours a day, 7 days a week, so peso payments are not limited by banking hours.
References
- Banco de México: SPEI, Sistema de Pagos Electrónicos Interbancarios
- Banco de México: SPID, Sistema de Pagos Interbancarios en Dólares
- BBVA México: Transferencias internacionales para empresas
This guide is general information for businesses, not financial, legal or tax advice. Rules, fees and timings were checked against the sources listed on the review date and may change.