What is Toss Pay, and how can international merchants accept it in South Korea?

South Korea is one of the world’s most mature mobile-first commerce markets, and local wallet-style payments are a standard part of the checkout experience. The broader South Korean mobile payment market is estimated at USD 44.38 billion in 2025 and projected to reach USD 68.70 billion by 2030.

Within that environment, Toss Pay stands out because it sits inside the Toss financial “super app,” which has become mainstream at a national scale: Toss surpassed 30 million users as of July 2025, representing nearly 60% of South Korea’s total population.

This article explains what Toss Pay is, how the Toss Pay payment processing typically works, and the most practical ways an international merchant can integrate and accept it for online payment.

What is Toss Pay?

Toss Pay is a South Korean payment method available in the Toss app that lets customers complete purchases on their mobile devices, often with a fast confirmation flow and funding options that include cards and bank transfers (exact options vary by implementation/provider).

It’s helpful to separate three related names that often get mixed up:

• Toss: the consumer-facing fintech super app.
• Toss Pay (also, tosspay): the wallet-style payment experience customers use at checkout.
• Toss Payments: the payments business/rails used for merchant acceptance and technical integration in some setups (often via payment service providers or direct integration).

Toss’s roots matter because they explain why “payments + transfers” are central to how people think about it. Toss was first launched in 2015 as a simple remittance/P2P money transfer service before expanding into broader financial and payment services.

Why global merchants should care about Toss Pay

For many Korean customers, local checkout means fast mobile approvals (often in-app), minimal re-entry of card details, familiar interfaces, and clear status updates for refunds and cancellations. 

With over 30 million users, Toss is widely recognised at checkout, and its roots in transfer and money transfers help explain why wallet-based payment behaviour is a default in Korea as mobile payments keep growing.

Toss Pay typically becomes most relevant when you sell online into South Korea and need a localised mix of payment methods.

Key features of Toss Pay

From a merchant perspective, here are consumer features that change checkout behaviour:

• Fast, app-native confirmation: Many Toss Pay implementations guide the buyer to confirm payment in the Toss app, which can reduce manual entry and streamline decision-making at checkout.
  
  
• Mobile-first experience: In common device-dependent flows, desktop shoppers may scan a QR code, while mobile shoppers may be redirected to the Toss app to confirm.
  
  
• Multiple funding paths (varies by provider): Toss Pay can support different underlying payment sources, such as cards and bank transfer-linked methods, which can make it flexible for consumers.
  
  
• Familiarity and trust in South Korea: Toss’s 30-million reach means many Korean customers already have the app and understand the interaction pattern.

How the Toss Pay payment process works

Customer checkout flow

A typical Toss Pay customer flow looks like this:

1. Customer selects Toss Pay as the payment method at checkout.
2. Customer authenticates/identifies as required by the flow (some implementations ask for details like phone number and date of birth; others rely more heavily on app-based confirmation).
3. The customer is prompted to confirm in the Toss app:
   • On the desktop, the buyer may scan a QR code with their phone.
   • On mobile, the buyer may be redirected to the Toss app to approve.
4. After approval, the customer returns to the merchant site/app and sees an order confirmation.

The flow is designed to minimise friction and keep the customer in a familiar Korean app for approval.

Merchant processing flow

A typical merchant-side flow (whether direct or via a payment provider) looks like this:

1. Merchant creates a payment request (amount, currency, order ID, customer context).
2. The system returns a payment session/token/redirect or QR payload for the buyer experience.
3. Merchant waits for payment confirmation via:
   • a return URL (customer redirects back), and
   • a server-to-server notification, such as a webhook/callback (recommended for reliability).
4. Merchant marks the order as paid and proceeds with fulfilment.
5. Funds settle to the merchant per the payment service provider (PSP)/acquirer’s settlement schedule and reporting structure.

If you choose a more direct integration with Toss Payments, note that they publish developer resources and Payment APIs/SDKs for integration workflows.

Toss Pay in online and in-store scenarios

How to accept Toss Pay as an international merchant

For most global merchants, the fastest way to accept Toss Pay is through a PSP that offers it as a supported South Korean payment method. In this setup, the PSP typically handles:

• local connectivity (often via partners/acquirers),
• redirect/QR and app-confirm flows,
• webhooks and status updates,
• refunds and reconciliation formats,
• compliance onboarding (KYB/KYC requirements as applicable).

Your selection of a PSP should be based on coverage, reliability, settlement options, and operational fit rather than brand familiarity.

What you should check:

• Does the PSP support Toss Pay for your merchant category and business model?
• What currencies are supported (KRW required for many local-method setups)?
• Settlement: timeline, settlement currency options, reporting granularity
• Refunds: full/partial, timing, how refunds map to order management
• Reliability: webhook retries, idempotency support, reconciliation tools
• Risk management: fraud tools, dispute support processes, data required at checkout

Integration considerations

1. Checkout UX and routing: Make Toss Pay visible to Korean shoppers (localisation + ordering of payment methods) and ensure a consistent mobile-first flow; test desktop QR and mobile redirect behaviours if used.
2. Currency and pricing: If your PSP requires KRW pricing for Toss Pay, decide whether you will display KRW prices to Korean users or convert at checkout (be careful about FX transparency and reconciliation).
3. Identity and approval steps: Some flows may require user inputs such as phone number/date of birth, while others rely on app confirmation patterns—validate what your PSP implements and ensure it doesn’t add unexpected friction.
4. Refund and cancellation operations: Ask questions about payment fulfilment, how partial refunds work, and how customer support confirms refund status.
5. Reconciliation: Ensure order ID mapping is consistent across PSP reports, webhook events, finance settlement statements.
6. Phased rollout: Start with one channel (e.g., mobile web), then expand to app/desktop once metrics are stable.

Benefits of accepting Toss Pay for merchants

If South Korea matters to your growth plan, Toss Pay acceptance can deliver concrete benefits:

• Lower checkout friction for Korean customers by letting them pay through a familiar app-confirm flow (streamlining the payment process).
• Competitive parity in South Korea, where mobile payments are a large and growing market.
• Better alignment with local payment expectations given Toss’s mainstream adoption.
• Strategic confidence in method maturity, supported by historical scale indicators like Toss’s reported cumulative transaction volume of up to 38 trillion KRW as of March 2019.

Conclusion

For international merchants, if you’re serious about scaling in South Korea, you should evaluate Toss Pay as part of your localised payment method mix. A sensible path is to start with a PSP-led integration, validate performance and operational handling, then deepen the integration only if South Korea volume and requirements justify it, especially in a market where mobile payments are expected to keep expanding through the coming years.