PIX vs SPEI: instant payments in Brazil and Mexico compared

Brazil and Mexico are the two largest payment markets in Latin America, and both have a central-bank instant payment rail that customers use instead of cards. In Brazil it is PIX, in Mexico it is SPEI. They look similar from a distance — account-to-account, real-time, no card network in the middle — but for a merchant or PSP they behave quite differently: how the customer identifies the payee, how payments are matched to orders, what happens with refunds and fraud, and which add-ons exist on top.

This guide compares PIX vs SPEI from the merchant side: what each system is, how a checkout flow works, how reconciliation and refunds differ, and what to ask a payment provider before going live in either country. It is informational: Nominal hub is a catalog, not a payment provider or intermediary.

PIX in one paragraph

PIX is the instant payment scheme created and operated by the Banco Central do Brasil (BCB). It went live in November 2020 and runs 24/7, every day of the year, with settlement in seconds through the central bank's instant payment system (SPI). A payer can send money using a PIX key — a CPF or CNPJ tax number, a phone number, an e-mail address or a random key — or by scanning a QR code, or by pasting the "copia e cola" code. Large financial institutions are required to offer PIX, which is why practically every Brazilian bank and wallet supports it. For an overview of providers see the PIX method page and payment providers in Brazil.

SPEI in one paragraph

SPEI (Sistema de Pagos Electrónicos Interbancarios) is Mexico's interbank electronic payment system, operated by Banco de México (Banxico) since 2004. It now runs around the clock and settles transfers between participants in seconds. The core identifier is the CLABE, an 18-digit standardized bank account number; transfers can also be addressed to a debit card number, and Banxico's newer services let banks route transfers to a mobile phone number. Every SPEI transfer carries a tracking key (clave de rastreo), and Banxico publishes an electronic payment receipt (CEP) that anyone can look up to confirm a transfer. Providers that support Mexico are grouped under payment providers in Mexico and bank transfer.

PIX vs SPEI: the key differences

Who runs it. Both are run by the central bank: BCB for PIX, Banxico for SPEI. The practical difference is age and product scope. PIX was designed in 2018–2020 as a consumer product with a brand, QR standard and mandatory participation. SPEI started as an interbank wholesale and retail transfer system and has had consumer layers (CoDi, then phone-number transfers) added later.

How the payer finds you. - PIX: a key or a QR code. Dynamic QR codes can carry the amount, an expiry time and a unique transaction ID, so the payer does not type anything. - SPEI: a CLABE number typed or copied into the banking app, plus amount and a free-text reference (concepto) and a numeric reference. QR-based request-to-pay exists (CoDi), but adoption has stayed limited compared with plain CLABE transfers.

Matching payments to orders. - PIX: the merchant's PSP generates a dynamic QR per order, so each incoming payment is tied to a transaction ID automatically. This is the main reason PIX checkout conversion is high and manual reconciliation is rare. - SPEI: customers frequently forget or mistype the reference. The common solution is a unique CLABE per customer or per order (often called virtual or referenced CLABE), issued by the PSP or bank. Every transfer to that CLABE belongs to one payer, whatever the reference says.

Speed and availability. Both are real-time and 24/7 for most participants. In practice the difference comes from the merchant's provider: how fast it receives the credit notification and posts a webhook, and whether it settles to you in real time, same day or T+1.

Limits. PIX limits are set by the payer's bank, with a central-bank rule that lowers the default limit for individuals at night (20:00–06:00); customers can request changes. SPEI has no single scheme-wide consumer cap; limits come from the sending bank and the account type. For high-ticket flows in either country, ask the provider about typical bank limits rather than assuming one number.

Refunds and disputes. Neither rail has a card-style chargeback. A refund is a new outgoing payment. - PIX has a formal refund function (devolução) linked to the original transaction, and a central-bank Special Return Mechanism (MED) that lets a payer's bank request the return of funds in cases of fraud or operational failure. Merchants whose accounts receive fraudulent PIX payments can have funds blocked while the case is reviewed. - SPEI returns are mainly technical (invalid or closed account). Customer-initiated disputes go through the banks, not through a standard scheme process, so the merchant's own refund policy and evidence matter more.

Verification of a payment. For PIX, the source of truth is the PSP's notification for the transaction ID. For SPEI, the tracking key plus the Banxico CEP lookup confirm that a transfer really settled — far better than a screenshot. Our article on confirming payments beyond screenshots explains why.

Recurring payments. PIX added an automatic recurring mode (Pix Automático) in 2025, which lets customers authorize periodic debits. In Mexico recurring billing is usually done with cards or direct debit (domiciliación) rather than SPEI.

Payouts. Both rails are widely used for payouts: marketplace sellers, gig workers, refunds and withdrawals. A PSP that collects PIX or SPEI should also be able to send to a PIX key or CLABE through the same API, which simplifies treasury.

A typical checkout flow

PIX 1. The customer selects PIX at checkout. 2. The PSP creates a charge and returns a dynamic QR code and a copy-paste code with an expiry time. 3. The customer pays in the banking app; the PSP receives the credit in seconds and sends a webhook. 4. The order is marked paid; settlement to the merchant follows the provider's schedule.

SPEI 1. The customer selects bank transfer / SPEI. 2. The PSP shows a CLABE (ideally unique to this customer or order), the exact amount and a reference. 3. The customer sends the transfer from the banking app. 4. The PSP detects the incoming SPEI credit on that CLABE, matches it and sends a webhook; partial or overpayments are handled by your rules.

The SPEI flow has one more step where customers drop off (copying an 18-digit number between apps), which is why good providers pre-fill copy buttons and show bank-specific instructions. Cash vouchers such as OXXO remain the fallback for unbanked customers in Mexico — see cash payments.

What to ask a PSP for Brazil or Mexico

• Is the account in your name or the provider's? Who is the receiving institution?
• PIX: dynamic QR with expiry and transaction ID, refund (devolução) by API, handling of MED blocks.
• SPEI: unique CLABE per customer or order, real-time webhook on credit, handling of partial payments and returns.
• Payouts to PIX keys and CLABEs from the same balance; cut-off times and fees.
• Settlement currency (BRL/MXN locally or USD abroad) and FX spread if you are a foreign merchant.
• KYB requirements and which business models are accepted. For high-risk verticals, confirm in writing.
• Uptime, status page and what happens when a participating bank is slow.

To compare providers, start with local payment method PSPs and filter by country. If you cannot find a fit, post a request describing your volume and GEO. For the broader picture of local methods across regions, read Local payment methods by region.

FAQ

Is PIX the same as SPEI? No. Both are central-bank instant payment systems, but PIX (Brazil) uses keys and QR codes with built-in transaction IDs, while SPEI (Mexico) is based on 18-digit CLABE account numbers and references.

Can a foreign company accept PIX or SPEI? Usually through a local payment provider or cross-border PSP that holds the local account and settles to you abroad. Direct participation requires a local licensed institution.

Do PIX and SPEI have chargebacks? No card-style chargebacks. PIX has a formal refund and a fraud return mechanism (MED); SPEI returns are mainly technical, and disputes are handled by banks.

Which converts better, PIX or SPEI? PIX checkout is generally simpler because dynamic QR codes remove manual entry. SPEI conversion depends heavily on how clearly the CLABE and amount are presented and whether the provider issues unique CLABEs.

How do I verify a SPEI payment? Use the tracking key (clave de rastreo) and check the electronic payment receipt (CEP) on Banxico's website, or rely on your provider's credit notification.