Create your Apple Pay merchant ID and certificates, and verify your domain.
- Apple Pay JS
To support Apple Pay on your website, you need to complete the setup, which includes registering a merchant ID, creating two certificates, and verifying your domain. Completing this setup enables you to use either or both web APIs: Apple Pay JS API or Payment Request API.
Follow the instructions in Configure Apple Pay on the Web. They guide you to create the following:
Merchant ID. An identifier you register with Apple that uniquely identifies your business as a merchant able to accept payments. This ID never expires, and can be used in multiple websites and iOS apps. See Create a merchant identifier for the setup steps.
Payment Processing Certificate. A certificate associated with your merchant ID, used to secure transaction data. Apple Pay servers use the certificate’s public key to encrypt payment data. You, or your payment service provider, use the private key to decrypt data to process payments. See Create a payment processing certificate for the setup steps.
Merchant Identity Certificate. A Transport Layer Security (TLS) certificate associated with your merchant ID, used to authenticate your sessions with the Apple Pay servers. The merchant identity certificate is only required for Apple Pay on the web; it isn't needed for apps. See Create a merchant identity certificate for the setup steps.
Register and verify your domain. You must register and verify the top-level domain and applicable subdomains that will use Apple Pay. You can register multiple domains under a single merchant ID. See Register a merchant domain and Verify a merchant domain.
While your merchant ID never expires, the payment processing certificate, merchant identity certificate, and domain verification do expire. See Maintaining Your Environment for more information.
Optionally, Set Up Xcode
By completing the setup for Apple Pay on the web, you already have everything you need to use Apple Pay on iOS and watchOS too. If you're developing apps that support Apple Pay, you'll need to enable Apple Pay in Xcode as a last step. See Configure Apple Pay (iOS, watchOS) for more information.
Use the Merchant ID in Multiple Environments
It is up to you to determine how many merchant IDs you need. Most merchants need only one and can use it for all environments: in multiple websites, iOS or watchOS apps, across test environments, and production environments.
However, you can create more than one merchant ID if you wish. Be sure to use the Payment Processing and Merchant Identity certificates created for the specific merchant ID. The certificates are valid only with their given merchant ID.