Apple Pay requires an Apple development and Authorize.net account.

First of all create account on https://developer.apple.com, after that register a Merchant ID:

1. In the “Account” section, select “Certificates, Identifiers & Profiles”.
2. Under “Identifiers”, select “Merchant IDs”.
3. Click the Add button (+) in the upper-right corner.
4. Enter a description and identifier, and click Continue.
5. Review the settings, and click Register.
6. Click Done.

If you have not already done so, you must create an Authorize.Net transaction key. This key is used to create a transaction-specific signature at your server. The signature is cross-checked by Authorize.Net servers when a transaction request is received, ensuring that no transaction is initiated by the consumer without your approval.

NOTE: Ensure that your transaction key is stored securely on your merchant server. Never store it within your app code on the device. If the key is compromised, generate a new key.

To create a transaction key:

1. In the Authorize.Net Merchant Interface(https://account.authorize.net/), navigate to Account > Settings > Security Settings > General Security Settings > API Login and Transaction Key.
2. Enter the answer to the secret question in the Secret Answer field.
3. Click Submit.

Apple Pay uses payment network tokenization. If your processor does not support payment network tokenization or if Authorize.Net does not support your payment processor's tokenization interface, you cannot sign up for Apple Pay through Authorize.Net.

To sign up for Apple Pay:

1. Log in to the Authorize.Net Merchant Interface.
2. Navigate to the Digital Payment Solutions section.
3. In the Apple Pay section, click Sign Up.

You must submit a Certificate Signing Request (CSR) to Apple in order to receive a necessary payment entitlement certificate.

To generate the CSR:

1. Log in to the Authorize.Net Merchant Interface
2. Navigate to Home > Digital Payments Solutions > Apple Pay.
3. Enter your Apple Merchant ID in the Apple merchant ID field. (The Apple Merchant ID that you enter must be identical to the one that you created at the Apple site. If it is different, Authorize.Net will not be able to to decrypt the payment data.)
4. Click Generate Apple CSR.

You must submit the CSR to Apple in order to receive the required payment entitlement certificate.

To submit the CSR file to Apple:

1. Navigate to the Apple Developer website and login if not already.
2. Once logged in, proceed to the “Account” section and then to the “Certificates, Identifiers & Profiles” section.
3. Under “Identifiers”, select “Merchant IDs”.
4. Select the merchant ID from the list, and click Edit.
5. In the “Payment Processing Certificates” section, click “Create Certificate”. Follow the instructions to obtain or generate your certificate signing request (CSR), and click Continue.
6. Click Choose File, select your CSR, and click Generate.

1. Navigate to the Apple Developer website and login if not already.
2. Once logged in, proceed to the “Account” section and then to the “Certificates, Identifiers & Profiles” section.
3. Under “Identifiers”, select “Merchant IDs”.
4. Select the merchant ID from the list, and click Edit.
5. In the Merchant Identity Certificate section, click Create Certificate. Follow the instructions to obtain or generate your certificate signing request (CSR), and click Continue.
6. Click Choose File, select your CSR, and click Generate.
7. Download the certificate by clicking Download, and click Done.
8. Double-click downloaded file to insert it into keychain access.app. this should automatically get appended to the existing entry for your Private key in keychain access.app
9. Right-click that certificate (probably named “Merchant ID: merchant….” from within keychain access.app (you may need to expand the private key entry to see the certificate under it) and select “Export 'Merchant ID merchant….' ”. This will default to exporting a xxxx.p12 file to your desktop.

Good 'How To' you can read here https://developer.apple.com/documentation/applepayjs

To use Apple Pay while developing your site, you'll need to use the Apple Pay Sandbox. Getting it set up takes just a few minutes.

1. If you don't have one already, create an Apple Developer account(https://developer.apple.com).
2. Log into iTunes Connect(https://itunesconnect.apple.com/).
3. Select Users and Roles, then select the Sandbox Testers link at the top of the page.
4. Next to “Testers”, click ⊕ to create a new test user. Fill out the page, taking note of the email and password you used, and click Save in the upper right.
5. On your test iOS device, open the Settings app and tap iCloud. If you're signed in, tap Sign Out at the bottom.
6. Log in using the new test credentials you just made.
7. Tap Back to return to the first page in Settings, then tap Wallet & Apple Pay.
8. Tap Add Credit or Debit Card, then when prompted to photograph your card tap Enter Card Details Manually.
9. Enter 4761 1200 1000 0492, expiration 11/2022, CVV 533 (this is a test Visa card; for more test cards see the Apple Pay Sandbox Guide(https://developer.apple.com/support/apple-pay-sandbox/)).

Contact Apple Pay and Auth.Net for info. Know more? Feel free to edit this page with info.

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