diff --git a/htdocs/comm/propal/class/api_proposals.class.php b/htdocs/comm/propal/class/api_proposals.class.php
index d153489dcc8..6d5a20b60bc 100644
--- a/htdocs/comm/propal/class/api_proposals.class.php
+++ b/htdocs/comm/propal/class/api_proposals.class.php
@@ -77,6 +77,9 @@ class Proposals extends DolibarrApi
 			throw new RestException(401, 'Access not allowed for login '.DolibarrApiAccess::$user->login);
 		}
 
+		// Add billing contacts ids
+                $this->propal->billing_contacts_ids = $this->propal->liste_contact(-1,'external',1,'BILLING');
+
 		$this->propal->fetchObjectLinked();
 		return $this->_cleanObjectDatas($this->propal);
 	}
@@ -156,6 +159,8 @@ class Proposals extends DolibarrApi
 				$obj = $db->fetch_object($result);
 				$proposal_static = new Propal($db);
 				if($proposal_static->fetch($obj->rowid)) {
+					// Add billing contacts ids
+                			$proposal_static->billing_contacts_ids = $proposal_static->liste_contact(-1,'external',1,'BILLING');
 					$obj_ret[] = $this->_cleanObjectDatas($proposal_static);
 				}
 				$i++;
@@ -708,7 +713,7 @@ class Proposals extends DolibarrApi
 
 		$object = parent::_cleanObjectDatas($object);
 
-        unset($object->note);
+        	unset($object->note);
 		unset($object->name);
 		unset($object->lastname);
 		unset($object->firstname);
diff --git a/htdocs/commande/class/api_orders.class.php b/htdocs/commande/class/api_orders.class.php
index c0e494a1684..f345282385c 100644
--- a/htdocs/commande/class/api_orders.class.php
+++ b/htdocs/commande/class/api_orders.class.php
@@ -76,6 +76,8 @@ class Orders extends DolibarrApi
 			throw new RestException(401, 'Access not allowed for login '.DolibarrApiAccess::$user->login);
 		}
 
+	// Add billing contacts ids
+        $this->commande->billing_contacts_ids = $this->commande->liste_contact(-1,'external',1,'BILLING');
         $this->commande->fetchObjectLinked();
 		return $this->_cleanObjectDatas($this->commande);
     }
@@ -159,6 +161,8 @@ class Orders extends DolibarrApi
                 $obj = $db->fetch_object($result);
                 $commande_static = new Commande($db);
                 if($commande_static->fetch($obj->rowid)) {
+ 		    // Add billing contacts ids
+                    $commande_static->billing_contacts_ids = $commande_static->liste_contact(-1,'external',1,'BILLING');
                     $obj_ret[] = $this->_cleanObjectDatas($commande_static);
                 }
                 $i++;
diff --git a/htdocs/compta/facture/class/api_invoices.class.php b/htdocs/compta/facture/class/api_invoices.class.php
index 2c744b8bda3..8a4979b2220 100644
--- a/htdocs/compta/facture/class/api_invoices.class.php
+++ b/htdocs/compta/facture/class/api_invoices.class.php
@@ -81,6 +81,8 @@ class Invoices extends DolibarrApi
 			throw new RestException(401, 'Access not allowed for login '.DolibarrApiAccess::$user->login);
 		}
 
+                // Add billing contacts ids
+                $this->invoice->billing_contacts_ids = $this->invoice->liste_contact(-1,'external',1,'BILLING');
 		$this->invoice->fetchObjectLinked();
 		return $this->_cleanObjectDatas($this->invoice);
 	}
@@ -176,6 +178,9 @@ class Invoices extends DolibarrApi
                 	$invoice_static->totaldeposits = $invoice_static->getSumDepositsUsed();
                 	$invoice_static->remaintopay = price2num($invoice_static->total_ttc - $invoice_static->totalpaid - $invoice_static->totalcreditnotes - $invoice_static->totaldeposits, 'MT');
 
+			// Add billing contacts ids
+                        $invoice_static->billing_contacts_ids = $invoice_static->liste_contact(-1,'external',1,'BILLING');
+
                 	$obj_ret[] = $this->_cleanObjectDatas($invoice_static);
                 }
                 $i++;