diff --git a/applications/accounting/src/main/java/org/apache/ofbiz/accounting/thirdparty/paypal/PayPalServices.java b/applications/accounting/src/main/java/org/apache/ofbiz/accounting/thirdparty/paypal/PayPalServices.java
index 3c1888fea3d..730676f69e2 100644
--- a/applications/accounting/src/main/java/org/apache/ofbiz/accounting/thirdparty/paypal/PayPalServices.java
+++ b/applications/accounting/src/main/java/org/apache/ofbiz/accounting/thirdparty/paypal/PayPalServices.java
@@ -484,7 +484,7 @@ public static Map<String, Object> getExpressCheckout(DispatchContext dctx, Map<S
                 return ServiceUtil.returnError(e.getMessage());
             }
         }
-        cart.addContactMech("ORDER_EMAIL", emailContactMechId);
+        cart.addContactMechId("ORDER_EMAIL", emailContactMechId);
 
         // Phone number
         String phoneNumber = decoder.get("PHONENUM");
@@ -508,7 +508,7 @@ public static Map<String, Object> getExpressCheckout(DispatchContext dctx, Map<S
             try {
                 outMap = dispatcher.runSync("createUpdatePartyTelecomNumber", inMap);
                 phoneContactId = (String) outMap.get("contactMechId");
-                cart.addContactMech("PHONE_BILLING", phoneContactId);
+                cart.addContactMechId("PHONE_BILLING", phoneContactId);
             } catch (GenericServiceException e) {
                 Debug.logError(e, MODULE);
             }
@@ -517,7 +517,7 @@ public static Map<String, Object> getExpressCheckout(DispatchContext dctx, Map<S
         String postalContactId = null;
         boolean needsShippingPurpose = true;
         // if the cart for some reason already has a billing address, we'll leave it be
-        boolean needsBillingPurpose = (cart.getContactMech("BILLING_LOCATION") == null);
+        boolean needsBillingPurpose = (cart.getContactMechId("BILLING_LOCATION") == null);
         Map<String, Object> postalMap = new HashMap<>();
         postalMap.put("toName", decoder.get("SHIPTONAME"));
         postalMap.put("address1", decoder.get("SHIPTOSTREET"));
diff --git a/applications/order/src/main/groovy/org/apache/ofbiz/order/order/CheckoutServices.groovy b/applications/order/src/main/groovy/org/apache/ofbiz/order/order/CheckoutServices.groovy
index eb69276ced6..f799ef1cc2b 100644
--- a/applications/order/src/main/groovy/org/apache/ofbiz/order/order/CheckoutServices.groovy
+++ b/applications/order/src/main/groovy/org/apache/ofbiz/order/order/CheckoutServices.groovy
@@ -86,7 +86,7 @@ Map createUpdateCustomerAndShippingAddress() {
     result.shipToPhoneContactMechId = serviceResultCUPTN.contactMechId
 
     if (shipToPhoneContactMechId) {
-        shoppingCart.addContactMech('PHONE_SHIPPING', shipToPhoneContactMechId)
+        shoppingCart.addContactMechId('PHONE_SHIPPING', shipToPhoneContactMechId)
     }
     // Create Update email address
     Map createUpdatePartyEmailCtx = emailAddressCtx
@@ -98,10 +98,10 @@ Map createUpdateCustomerAndShippingAddress() {
     result.emailContactMechId = serviceResultCUPEM.contactMechId
     result.partyId = partyId
     if (parameters.emailContactMechId) {
-        shoppingCart.addContactMech('ORDER_EMAIL', parameters.emailContactMechId)
+        shoppingCart.addContactMechId('ORDER_EMAIL', parameters.emailContactMechId)
     }
     shoppingCart.setUserLogin(userLogin, dispatcher)
-    shoppingCart.addContactMech('SHIPPING_LOCATION', parameters.shipToContactMechId)
+    shoppingCart.addContactMechId('SHIPPING_LOCATION', parameters.shipToContactMechId)
     shoppingCart.setAllShippingContactMechId(parameters.shipToContactMechId)
     shoppingCart.setOrderPartyId(partyId)
     return result
@@ -149,7 +149,7 @@ Map createUpdateBillingAddressAndPaymentMethod() {
     parameters.billToContactMechId = serviceResultCUBA.contactMechId
     result.contactMechId = serviceResultCUBA.contactMechId
     if (parameters.billToContactMechId) {
-        shoppingCart.addContactMech('BILLING_LOCATION', parameters.billToContactMechId)
+        shoppingCart.addContactMechId('BILLING_LOCATION', parameters.billToContactMechId)
     }
     // Create Update Billing Telecom Number
     Map createUpdatePartyTelecomNumberCtx = billToPhoneContext
@@ -165,7 +165,7 @@ Map createUpdateBillingAddressAndPaymentMethod() {
     String billToPhoneContactMechId = serviceResultCUPTN.contactMechId
     result.billToPhoneContactMechId = serviceResultCUPTN.contactMechId
     if (billToPhoneContactMechId) {
-        shoppingCart.addContactMech('PHONE_BILLING', billToPhoneContactMechId)
+        shoppingCart.addContactMechId('PHONE_BILLING', billToPhoneContactMechId)
     }
     // Create Update credit card
     Map creditCartCtx = parameters
diff --git a/applications/order/src/main/java/org/apache/ofbiz/order/shoppingcart/ShoppingCart.java b/applications/order/src/main/java/org/apache/ofbiz/order/shoppingcart/ShoppingCart.java
index 431c6cfb12a..196cb99c164 100644
--- a/applications/order/src/main/java/org/apache/ofbiz/order/shoppingcart/ShoppingCart.java
+++ b/applications/order/src/main/java/org/apache/ofbiz/order/shoppingcart/ShoppingCart.java
@@ -139,7 +139,7 @@ public class ShoppingCart implements Iterable<ShoppingCartItem>, Serializable {
     private long nextGroupNumber = 1;
     private List<CartPaymentInfo> paymentInfo = new LinkedList<>();
     private List<CartShipInfo> shipInfo = new LinkedList<>();
-    private Map<String, String> contactMechIdsMap = new HashMap<>();
+    private Map<String, Set<String>> contactMechIdsMap = new HashMap<>();
     private Map<String, String> orderAttributes = new HashMap<>();
     private Map<String, Object> attributes = new HashMap<>(); // user defined attributes
     // Lists of internal/public notes: when the order is stored they are transformed into OrderHeaderNotes
@@ -3465,28 +3465,41 @@ public BigDecimal getGiftCardPaymentPreferenceTotal() {
     }
 
     /** Add a contact mech to this purpose; the contactMechPurposeTypeId is required */
-    public void addContactMech(String contactMechPurposeTypeId, String contactMechId) {
+    public void addContactMechId(String contactMechPurposeTypeId, String contactMechId) {
         if (contactMechPurposeTypeId == null) {
             throw new IllegalArgumentException("You must specify a contactMechPurposeTypeId to add a ContactMech");
         }
-        contactMechIdsMap.put(contactMechPurposeTypeId, contactMechId);
+        UtilMisc.addToSetInMap(contactMechId, contactMechIdsMap, contactMechPurposeTypeId);
     }
 
     /** Get the contactMechId for this cart given the contactMechPurposeTypeId */
-    public String getContactMech(String contactMechPurposeTypeId) {
-        return contactMechIdsMap.get(contactMechPurposeTypeId);
+    public String getContactMechId(String contactMechPurposeTypeId) {
+        return UtilValidate.isNotEmpty(getContactMechIds(contactMechPurposeTypeId))
+                ? getContactMechIds(contactMechPurposeTypeId).get(0)
+                : null;
     }
 
-    /** Remove the contactMechId from this cart given the contactMechPurposeTypeId */
-    public String removeContactMech(String contactMechPurposeTypeId) {
-        return contactMechIdsMap.remove(contactMechPurposeTypeId);
+    /** Get the contactMechIds list for this cart given the contactMechPurposeTypeId */
+    public List<String> getContactMechIds(String contactMechPurposeTypeId) {
+        Set<String> contactMechIds = contactMechIdsMap.get(contactMechPurposeTypeId);
+        return contactMechIds != null
+                ? new ArrayList<>(contactMechIds)
+                : List.of();
+    }
+
+    /** Remove the contactMechIds list from this cart given the contactMechPurposeTypeId */
+    public List<String> removeContactMechId(String contactMechPurposeTypeId) {
+        Set<String> contactMechIds = contactMechIdsMap.remove(contactMechPurposeTypeId);
+        return contactMechIds != null
+                ? new ArrayList<>(contactMechIds)
+                : List.of();
     }
 
     /**
      * Gets order contact mech ids.
      * @return the order contact mech ids
      */
-    public Map<String, String> getOrderContactMechIds() {
+    public Map<String, Set<String>> getOrderContactMechIds() {
         return this.contactMechIdsMap;
     }
 
@@ -4616,17 +4629,15 @@ public List<GenericValue> makeAllOrderItemSurveyResponses() {
     public List<GenericValue> makeAllOrderContactMechs() {
         List<GenericValue> allOrderContactMechs = new LinkedList<>();
 
-        Map<String, String> contactMechIds = this.getOrderContactMechIds();
-
+        Map<String, Set<String>> contactMechIds = this.getOrderContactMechIds();
         if (contactMechIds != null) {
-            for (Map.Entry<String, String> entry : contactMechIds.entrySet()) {
-                GenericValue orderContactMech = getDelegator().makeValue("OrderContactMech");
-                orderContactMech.set("contactMechPurposeTypeId", entry.getKey());
-                orderContactMech.set("contactMechId", entry.getValue());
-                allOrderContactMechs.add(orderContactMech);
+            for (Map.Entry<String, Set<String>> entry : contactMechIds.entrySet()) {
+                entry.getValue().forEach(contactMechId ->
+                        allOrderContactMechs.add(getDelegator().makeValue("OrderContactMech",
+                                Map.of("contactMechPurposeTypeId", entry.getKey(),
+                                        "contactMechId", contactMechId))));
             }
         }
-
         return allOrderContactMechs;
     }
 
diff --git a/applications/order/src/main/java/org/apache/ofbiz/order/shoppingcart/ShoppingCartServices.java b/applications/order/src/main/java/org/apache/ofbiz/order/shoppingcart/ShoppingCartServices.java
index d25583c86b3..20f2dd8493b 100644
--- a/applications/order/src/main/java/org/apache/ofbiz/order/shoppingcart/ShoppingCartServices.java
+++ b/applications/order/src/main/java/org/apache/ofbiz/order/shoppingcart/ShoppingCartServices.java
@@ -329,7 +329,7 @@ public static Map<String, Object> loadCartFromOrder(DispatchContext dctx, Map<St
         }
         if (UtilValidate.isNotEmpty(orderContactMechs)) {
             for (GenericValue orderContactMech : orderContactMechs) {
-                cart.addContactMech(orderContactMech.getString("contactMechPurposeTypeId"), orderContactMech.getString("contactMechId"));
+                cart.addContactMechId(orderContactMech.getString("contactMechPurposeTypeId"), orderContactMech.getString("contactMechId"));
             }
         }
         List<GenericValue> orderItemShipGroupList = orh.getOrderItemShipGroups();