iOS 18 Tap to Cash Biometric Requirements

Apple’s iOS 18 introduces Tap to Cash, a feature that allows users to send and receive Apple Cash simply by holding two iPhone devices near each other without sharing phone numbers or email addresses. To ensure unauthorized transactions do not take place, Apple mandates biometric authentication before any funds leave an account. Depending on the iPhone model being used, the sender must authenticate using either Face ID or Touch ID to authorize the transaction.

Required Biometric Authentication

Before a Tap to Cash payment is processed, the sender must authenticate using their device's native biometric system:

  • Face ID: On iPhone X and newer models (excluding SE series), users must authenticate via facial recognition. When initiating the transfer, the device prompts the user to double-click the side button and glance at the screen to verify their identity.
  • Touch ID: On iPhone SE models that utilize a Home button, users authenticate by placing their registered fingerprint on the Touch ID sensor.

If biometric recognition fails or is unavailable, the system defaults to requiring the device’s passcode.

How the Authentication Flow Works

  1. Initiate the Transfer: The sender opens the Apple Wallet app, selects their Apple Cash card, and taps the Send or Request option (or selects Tap to Cash directly from the Control Center).
  2. Enter Amount: The user inputs the exact dollar amount they wish to send.
  3. Biometric Confirmation: The device prompts for confirmation. The user double-clicks the side button and completes authentication using Face ID or Touch ID.
  4. Device Proximity: Once the biometric check succeeds, the user holds the top of their iPhone near the recipient's iPhone.
  5. Completion: The devices connect using near-field communication (NFC), and the Apple Cash transfer is completed securely without exchanging personal contact details.

This biometric requirement ensures that physical proximity alone cannot trigger a payment, preventing accidental transfers or unauthorized access if a device is unlocked or handled by another person.