diff --git a/pkg/rid/models/api/v1/conversions.go b/pkg/rid/models/api/v1/conversions.go
index a5bda3906..c3fdd6711 100644
--- a/pkg/rid/models/api/v1/conversions.go
+++ b/pkg/rid/models/api/v1/conversions.go
@@ -163,20 +163,29 @@ func ToIdentificationServiceArea(i *ridmodels.IdentificationServiceArea) *restap
 	return result
 }
 
-// ToSubscriberToNotify converts a Subscription to a SubscriberToNotify RID v1
-// REST model for API consumption.
-func ToSubscriberToNotify(s *ridmodels.Subscription) *restapi.SubscriberToNotify {
-	notifIndex := restapi.SubscriptionNotificationIndex(s.NotificationIndex)
-	subID := restapi.SubscriptionUUID(s.ID.String())
-	return &restapi.SubscriberToNotify{
-		Url: restapi.URL(s.URL),
-		Subscriptions: []restapi.SubscriptionState{
-			{
-				NotificationIndex: &notifIndex,
-				SubscriptionId:    &subID,
-			},
-		},
+// MakeSubscribersToNotify groups the passed subscriptions by their callback URL,
+// returning a collection of subscribers to notify that contains one entry per distinct callback URL.
+func MakeSubscribersToNotify(subscriptions []*ridmodels.Subscription) []restapi.SubscriberToNotify {
+	subscriptionsByURL := map[string][]restapi.SubscriptionState{}
+	for _, sub := range subscriptions {
+		notifIdx := restapi.SubscriptionNotificationIndex(sub.NotificationIndex)
+		subID := restapi.SubscriptionUUID(sub.ID)
+		subState := restapi.SubscriptionState{
+			SubscriptionId:    &subID,
+			NotificationIndex: &notifIdx,
+		}
+		subscriptionsByURL[sub.URL] = append(subscriptionsByURL[sub.URL], subState)
+	}
+
+	result := []restapi.SubscriberToNotify{}
+	for url, states := range subscriptionsByURL {
+		result = append(result, restapi.SubscriberToNotify{
+			Url:           restapi.URL(url),
+			Subscriptions: states,
+		})
 	}
+
+	return result
 }
 
 // ToSubscription converts a subscription business object to a Subscription RID
diff --git a/pkg/rid/server/v1/isa_handler.go b/pkg/rid/server/v1/isa_handler.go
index 5bf890c88..e60b61a35 100644
--- a/pkg/rid/server/v1/isa_handler.go
+++ b/pkg/rid/server/v1/isa_handler.go
@@ -123,10 +123,7 @@ func (s *Server) CreateIdentificationServiceArea(ctx context.Context, req *resta
 		}
 	}
 
-	apiSubscribers := make([]restapi.SubscriberToNotify, 0, len(subscribers))
-	for _, subscriber := range subscribers {
-		apiSubscribers = append(apiSubscribers, *apiv1.ToSubscriberToNotify(subscriber))
-	}
+	apiSubscribers := apiv1.MakeSubscribersToNotify(subscribers)
 
 	return restapi.CreateIdentificationServiceAreaResponseSet{Response200: &restapi.PutIdentificationServiceAreaResponse{
 		ServiceArea: *apiv1.ToIdentificationServiceArea(insertedISA),
@@ -210,10 +207,7 @@ func (s *Server) UpdateIdentificationServiceArea(ctx context.Context, req *resta
 		}
 	}
 
-	apiSubscribers := make([]restapi.SubscriberToNotify, 0, len(subscribers))
-	for _, subscriber := range subscribers {
-		apiSubscribers = append(apiSubscribers, *apiv1.ToSubscriberToNotify(subscriber))
-	}
+	apiSubscribers := apiv1.MakeSubscribersToNotify(subscribers)
 
 	return restapi.UpdateIdentificationServiceAreaResponseSet{Response200: &restapi.PutIdentificationServiceAreaResponse{
 		ServiceArea: *apiv1.ToIdentificationServiceArea(insertedISA),
@@ -264,10 +258,7 @@ func (s *Server) DeleteIdentificationServiceArea(ctx context.Context, req *resta
 		}
 	}
 
-	apiSubscribers := make([]restapi.SubscriberToNotify, 0, len(subscribers))
-	for _, subscriber := range subscribers {
-		apiSubscribers = append(apiSubscribers, *apiv1.ToSubscriberToNotify(subscriber))
-	}
+	apiSubscribers := apiv1.MakeSubscribersToNotify(subscribers)
 
 	return restapi.DeleteIdentificationServiceAreaResponseSet{Response200: &restapi.DeleteIdentificationServiceAreaResponse{
 		ServiceArea: *apiv1.ToIdentificationServiceArea(isa),