diff --git a/GoCardless/Resources/BankAuthorisation.cs b/GoCardless/Resources/BankAuthorisation.cs
index 89d964c..6f6a3c1 100644
--- a/GoCardless/Resources/BankAuthorisation.cs
+++ b/GoCardless/Resources/BankAuthorisation.cs
@@ -73,6 +73,20 @@ public class BankAuthorisation
         /// <summary>
         /// URL that the payer can be redirected to after authorising the
         /// payment.
+        /// 
+        /// On completion of bank authorisation, the query parameter of either
+        /// `outcome=success` or `outcome=failure` will be
+        /// appended to the `redirect_uri` to indicate the result of the bank
+        /// authorisation. If the bank authorisation is
+        /// expired, the query parameter `outcome=timeout` will be appended to
+        /// the `redirect_uri`, in which case you should
+        /// prompt the user to try the bank authorisation step again.
+        /// 
+        /// The `redirect_uri` you provide should handle the `outcome` query
+        /// parameter for displaying the result of the
+        /// bank authorisation as outlined above.
+        /// 
+        /// Defaults to `https://pay.gocardless.com/billing/static/thankyou`.
         /// </summary>
         [JsonProperty("redirect_uri")]
         public string RedirectUri { get; set; }
diff --git a/GoCardless/Services/BankAuthorisationService.cs b/GoCardless/Services/BankAuthorisationService.cs
index 4dcdd4b..06286d5 100644
--- a/GoCardless/Services/BankAuthorisationService.cs
+++ b/GoCardless/Services/BankAuthorisationService.cs
@@ -144,6 +144,20 @@ public class BankAuthorisationLinks
         /// <summary>
         /// URL that the payer can be redirected to after authorising the
         /// payment.
+        /// 
+        /// On completion of bank authorisation, the query parameter of either
+        /// `outcome=success` or `outcome=failure` will be
+        /// appended to the `redirect_uri` to indicate the result of the bank
+        /// authorisation. If the bank authorisation is
+        /// expired, the query parameter `outcome=timeout` will be appended to
+        /// the `redirect_uri`, in which case you should
+        /// prompt the user to try the bank authorisation step again.
+        /// 
+        /// The `redirect_uri` you provide should handle the `outcome` query
+        /// parameter for displaying the result of the
+        /// bank authorisation as outlined above.
+        /// 
+        /// Defaults to `https://pay.gocardless.com/billing/static/thankyou`.
         /// </summary>
         [JsonProperty("redirect_uri")]
         public string RedirectUri { get; set; }