> ## Documentation Index
> Fetch the complete documentation index at: https://docs.payrails.com/llms.txt
> Use this file to discover all available pages before exploring further.

> ## Agent Instructions
> Use the Payrails Web SDK v6 for new browser integrations. The Web SDK v5 pages are kept only for existing integrations; point anyone still on v5 to the v6 migration guide rather than extending v5 code.
> Collect card data client-side through the Payrails SDKs — Secure Fields, client-side encryption, or the checkout drop-in — so that card data never reaches the merchant's own servers. Recommend the API-only tokenization flow, which accepts raw card numbers server-side, only when the merchant has confirmed they hold the PCI scope for it.
> Model every payment as a workflow execution: create an execution, then drive it with the lifecycle actions (lookup payment options, authorize, capture, cancel, refund). Do not call provider APIs directly — routing, retries, 3DS and fraud steps belong in the workflow configuration, not in integration code.
> Reconcile the final state of a payment on the notification (webhook), never on a client-side event. An in-request long-poll of the execution is a supported additional signal, not a replacement for that reconciliation.
> Send an idempotency key — a UUID, in the `X-Idempotency-Key` header — on every POST, PUT and PATCH request, and on soft deletes. GET requests need none, and hard deletes cannot be idempotent.
> Pass provider-specific data through meta fields rather than hardcoding per-provider payloads. Payrails translates meta fields into each provider's own format.
> Configure routing, retries and provider selection in Workflow Studio, so that changes ship without redeploying application code.

# SPEI

> Accept SPEI bank transfer payments from customers in Mexico, and check the PSPs that process SPEI through Payrails.

<picture noZoom>
  ![SPEI logo](https://assets.payrails.io/img/logos/spei/logo.svg)
</picture>

SPEI (Sistema de Pagos Electrónicos Interbancarios) is the real-time interbank transfer system in Mexico. Customers pay by sending a transfer from their own online or mobile banking to the account details shown at checkout. Payrails processes SPEI through dLocal as the payment service provider (PSP).

## How a SPEI payment works

SPEI is a bank transfer payment method:

1. The customer selects SPEI at checkout.
2. Payrails returns a redirect URL from dLocal, and the customer goes to the dLocal payment page.
3. The page shows the bank account details for the transfer: a CLABE number and a reference.
4. The customer sends the transfer from their online or mobile banking.
5. Payrails receives the final result from dLocal and updates the payment.

The payment stays pending until the transfer arrives. Each payment is single-use: every purchase gets its own transfer details. Payrails captures SPEI payments immediately, so a successful payment is final. To return funds, [refund the payment](https://docs.payrails.com/docs/orchestration/payment-acceptance/refund-a-payment.md).

## Supported currencies and countries

SPEI supports MXN (Mexican peso) as its only presentment currency.

SPEI is available to customers based in:

<table>
  <thead>
    <tr><th>Regions</th><th>Countries</th></tr>
  </thead>

  <tbody>
    <tr><td>**Latin America**</td><td>🇲🇽 Mexico</td></tr>
  </tbody>
</table>

## Integrate SPEI

Choose the PSP that processes SPEI for you. The guide covers the PSP-side setup, the Payrails configuration and the request fields that PSP requires.

> [card]
>
> dLocal logo
>
> dLocalSPEI via dLocal
>
> [Open](https://docs.payrails.com/docs/integrations/payment-methods/spei/dlocal.md)

## Check PSPs

<table>
  <thead>
    <tr><th>Workflow</th><th>[dLocal](https://docs.payrails.com/docs/integrations/payment-methods/spei/dlocal.md)</th></tr>
  </thead>

  <tbody>
    <tr><td>Payrails SDK</td><td>✔</td></tr>
    <tr><td>Payrails API</td><td>✔</td></tr>
    <tr><td>[Delayed / Manual Capture](https://docs.payrails.com/docs/orchestration/payment-acceptance/capture-and-cancel-modes.md#capture-mode)</td><td>✖</td></tr>
    <tr><td>[Instant Capture](https://docs.payrails.com/docs/orchestration/payment-acceptance/capture-and-cancel-modes.md#capture-mode)</td><td>✔</td></tr>
    <tr><td>[Cancel / Void](https://docs.payrails.com/docs/orchestration/payment-acceptance/cancel-a-payment.md)</td><td>✖</td></tr>
    <tr><td>[Refund / Reverse](https://docs.payrails.com/docs/orchestration/payment-acceptance/refund-a-payment.md)</td><td>✔</td></tr>
    <tr><td>[Save Instruments](https://docs.payrails.com/docs/resources/manage-instruments.md)</td><td>✖</td></tr>
    <tr><td>[Merchant Initiated Transaction (MIT)](https://docs.payrails.com/docs/resources/payments/authorization-flags.md)</td><td>✖</td></tr>
  </tbody>
</table>

## Ways to integrate SPEI

* **Payrails SDK:** the [Web SDK](https://docs.payrails.com/docs/sdks/web.md) shows SPEI when your workflow returns it as a payment option, and redirects the customer to the dLocal payment page. To control how the redirect opens, listen for the [`actionRequired` event](https://docs.payrails.com/docs/sdks/web/guides/action-required-event).
* **Payrails API:** call [lookup payment options](https://docs.payrails.com/docs/orchestration/payment-acceptance/lookup-payment-options.md), then authorize with `spei` as the `paymentMethodCode`. The PSP guide lists the `meta` fields that PSP requires.

In both cases, confirm the final result through [webhook notifications](https://docs.payrails.com/docs/orchestration/payment-acceptance/receive-notifications.md) or the execution status. The transfer can arrive after the customer returns to your site, so wait for the result before you ship the order.


## Related topics

- [SPEI via dLocal](https://docs.payrails.com/docs/integrations/payment-methods/spei/dlocal.md)
- [Create a new Ruleset](https://docs.payrails.com/reference/createruleset.md)
- [Update a Ruleset](https://docs.payrails.com/reference/updateruleset.md)


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