> For the complete documentation index, see [llms.txt](https://docs.payments.thalescloud.io/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://docs.payments.thalescloud.io/click-to-pay-merchants/use-cases/readme.md).

# Overview

Click to Pay is an online checkout solution based on EMV® Secure Remote Commerce (SRC) standards.

Our pre-integrated solution manages the complexity. It helps you deliver a secure, low-friction checkout experience.

<figure><img src="/files/gFE0TgUXOX0dWDsI7s1p" alt=""><figcaption><p>Click to Pay solution components.</p></figcaption></figure>

### How Click to Pay works

On first use, the end user signs up and enrolls a payment card and shipping address.

On subsequent purchases, the end user signs in with their registered email address or mobile number. They then select a card and complete checkout quickly.

{% hint style="info" %}
Some flows depend on whether the device is recognized (for example, when the end user previously selected **Remember me**).
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| Use Case                                                                                                                                                            | Description                                                                                                                                                                                                                                                                         |
| ------------------------------------------------------------------------------------------------------------------------------------------------------------------- | ----------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------- |
| [Existing User on Recognized Device](https://developer.mastercard.com/mastercard-checkout-solutions/documentation/use-cases/click-to-pay/returninguser_recognized/) | Consumers with a Click to Pay profile and using a recognized device (i.e. they selected “Remember me” during previous checkout with this device) will have a frictionless experience. In this case, consumers just need to select the payment card to use for the transaction.      |
| [Existing User on Unrecognized Device](https://developer.mastercard.com/mastercard-checkout-solutions/documentation/use-cases/click-to-pay/repeatuser_newdevice/)   | Consumers who have a Click to Pay profile but are checking out using an unrecognized device, will need to enter the email address associated with their Click to Pay profile and verify their identity with a one-time-passcode (OTP) sent to their email address or mobile number. |
| [First Time User](https://developer.mastercard.com/mastercard-checkout-solutions/documentation/use-cases/click-to-pay/firsttimeuser_usecase/)                       | Consumers who have not yet registered with Click to Pay need to enter their payment card and shipping address before checkout.                                                                                                                                                      |

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### <mark style="color:$primary;">Start Building</mark> with Thales

Accelerate your payment solutions and deliver secure, scalable experiences today.

<a href="https://lp.thalesgroup.com/dev-portal" class="button primary">Contact Us</a>&#x20;

&#x20;
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