diff --git a/Pay/PaySession.swift b/Pay/PaySession.swift
index d3cb65f2..d47d3551 100644
--- a/Pay/PaySession.swift
+++ b/Pay/PaySession.swift
@@ -189,7 +189,7 @@ extension PaySession: PKPaymentAuthorizationControllerDelegate {
     // -------------------------------------------------------
     //  MARK: - PKPaymentAuthorizationControllerDelegate -
     //
-    @available(iOS 11.0, *)
+    @available(iOS 11.0, watchOS 4.0, *)
     public func paymentAuthorizationController(_ controller: PKPaymentAuthorizationController, didAuthorizePayment payment: PKPayment, handler completion: @escaping (PKPaymentAuthorizationResult) -> Void) {
         self.paymentAuthorizationController(controller, didAuthorizePayment: payment) { (status: PKPaymentAuthorizationStatus) in
             let result = PKPaymentAuthorizationResult(status: status, errors: nil)
@@ -229,7 +229,7 @@ extension PaySession: PKPaymentAuthorizationControllerDelegate {
         })
     }
     
-    @available(iOS 11.0, *)
+    @available(iOS 11.0, watchOS 4.0, *)
     public func paymentAuthorizationController(_ controller: PKPaymentAuthorizationController, didSelectShippingContact contact: PKContact, handler completion: @escaping (PKPaymentRequestShippingContactUpdate) -> Void) {
         
         self.paymentAuthorizationController(controller, didSelectShippingContact: contact) { status, shippingMethod, summaryItems in
@@ -312,7 +312,7 @@ extension PaySession: PKPaymentAuthorizationControllerDelegate {
         })
     }
     
-    @available(iOS 11.0, *)
+    @available(iOS 11.0, watchOS 4.0, *)
     public func paymentAuthorizationController(_ controller: PKPaymentAuthorizationController, didSelectShippingMethod shippingMethod: PKShippingMethod, handler completion: @escaping (PKPaymentRequestShippingMethodUpdate) -> Void) {
         self.paymentAuthorizationController(controller, didSelectShippingMethod: shippingMethod) { status, summaryItems in
             let result    = PKPaymentRequestShippingMethodUpdate(paymentSummaryItems: summaryItems)