diff --git a/phpunit/functional/TicketCostTest.php b/phpunit/functional/TicketCostTest.php
new file mode 100644
index 00000000000..198f744c75d
--- /dev/null
+++ b/phpunit/functional/TicketCostTest.php
@@ -0,0 +1,218 @@
+<?php
+
+/**
+ * ---------------------------------------------------------------------
+ *
+ * GLPI - Gestionnaire Libre de Parc Informatique
+ *
+ * http://glpi-project.org
+ *
+ * @copyright 2015-2024 Teclib' and contributors.
+ * @copyright 2003-2014 by the INDEPNET Development Team.
+ * @licence   https://www.gnu.org/licenses/gpl-3.0.html
+ *
+ * ---------------------------------------------------------------------
+ *
+ * LICENSE
+ *
+ * This file is part of GLPI.
+ *
+ * This program is free software: you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation, either version 3 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program.  If not, see <https://www.gnu.org/licenses/>.
+ *
+ * ---------------------------------------------------------------------
+ */
+
+namespace tests\units;
+
+use DbTestCase;
+use Item_Ticket;
+use Ticket;
+use TicketCost;
+use Computer;
+
+class TicketCostTest extends DbTestCase
+{
+    private function getNewTicket()
+    {
+        return $this->createItem(Ticket::class, [
+            'name' => 'my ticket name',
+            'entities_id' => $this->getTestRootEntity(true),
+            '_users_id_assign'   => getItemByTypeName('User', 'tech', true),
+            'content'            => '',
+        ]);
+    }
+
+    private function getNewComputer()
+    {
+        return $this->createItem(Computer::class, [
+            'name' => 'my computer name',
+            'entities_id' => $this->getTestRootEntity(true),
+        ]);
+    }
+
+    private function getNewTicketCost(array $values = [])
+    {
+        return $this->createItem(TicketCost::class, [
+            'name' => $values['name'] ?? 'my ticket cost name',
+            'entities_id' => $this->getTestRootEntity(true),
+            'tickets_id' => $values['tickets_id'],
+            'cost_time' => $values['cost_time'] ?? 0.,
+            'cost_fixed' => $values['cost_fixed'] ?? 0.,
+            'cost_material' => $values['cost_material'] ?? 0.,
+            'actiontime' => $values['actiontime'] ?? 1,
+        ]);
+    }
+
+    private function getNewItemTicket(array $values = [])
+    {
+        return $this->createItem(Item_Ticket::class, [
+            'tickets_id' => $values['tickets_id'],
+            'itemtype' => $values['itemtype'] ?? 'Computer',
+            'items_id' => $values['items_id'],
+        ]);
+    }
+
+    public function testAddCost()
+    {
+        $computer = $this->getNewComputer();
+        $this->assertSame(0., floatval($computer->fields['ticket_tco']));
+        $ticket = $this->getNewTicket();
+        $this->getNewItemTicket(
+            [
+                'tickets_id' => $ticket->getID(),
+                'itemtype' => 'Computer',
+                'items_id' => $computer->getID(),
+            ]
+        );
+        $computer->getFromDB($computer->getID());
+        $this->assertSame(0., floatval($computer->fields['ticket_tco']));
+        $this->getNewTicketCost(
+            [
+                'tickets_id' => $ticket->getID(),
+                'cost_material' => 10.
+            ]
+        );
+        $computer->getFromDB($computer->getID());
+        $this->assertSame(10., floatval($computer->fields['ticket_tco']));
+        $this->getNewTicketCost(
+            [
+                'tickets_id' => $ticket->getID(),
+                'cost_fixed' => 10.,
+                'cost_material' => 80.
+            ]
+        );
+        $computer->getFromDB($computer->getID());
+        $this->assertSame(100., floatval($computer->fields['ticket_tco']));
+    }
+
+    public function testRemoveCost()
+    {
+        $computer = $this->getNewComputer();
+        $this->assertSame(0., floatval($computer->fields['ticket_tco']));
+        $ticket = $this->getNewTicket();
+        $this->getNewItemTicket(
+            [
+                'tickets_id' => $ticket->getID(),
+                'itemtype' => 'Computer',
+                'items_id' => $computer->getID(),
+            ]
+        );
+        $ticketcost = $this->getNewTicketCost(
+            [
+                'tickets_id' => $ticket->getID(),
+                'cost_fixed' => 10.,
+                'cost_material' => 80.
+            ]
+        );
+        $computer->getFromDB($computer->getID());
+        $this->assertSame(90., floatval($computer->fields['ticket_tco']));
+        $ticketcost->delete(['id' => $ticketcost->getID()], true);
+        $computer->getFromDB($computer->getID());
+        $this->assertSame(0., floatval($computer->fields['ticket_tco']));
+    }
+
+    public function testAddItem()
+    {
+        $computer = $this->getNewComputer();
+        $this->assertSame(0., floatval($computer->fields['ticket_tco']));
+        $ticket = $this->getNewTicket();
+        $this->getNewTicketCost(
+            [
+                'tickets_id' => $ticket->getID(),
+                'cost_fixed' => 140.,
+                'cost_material' => 860.
+            ]
+        );
+        $this->getNewTicketCost(
+            [
+                'tickets_id' => $ticket->getID(),
+                'cost_fixed' => 80.,
+                'cost_material' => 20.
+            ]
+        );
+        $this->getNewItemTicket(
+            [
+                'tickets_id' => $ticket->getID(),
+                'itemtype' => 'Computer',
+                'items_id' => $computer->getID(),
+            ]
+        );
+        $computer->getFromDB($computer->getID());
+        $this->assertSame(1100., floatval($computer->fields['ticket_tco']));
+    }
+
+    public function testItemInMultipleTicket()
+    {
+        $computer = $this->getNewComputer();
+        $this->assertSame(0., floatval($computer->fields['ticket_tco']));
+
+        $ticket = $this->getNewTicket();
+        $this->getNewItemTicket(
+            [
+                'tickets_id' => $ticket->getID(),
+                'itemtype' => 'Computer',
+                'items_id' => $computer->getID(),
+            ]
+        );
+        $computer->getFromDB($computer->getID());
+        $this->assertSame(0., floatval($computer->fields['ticket_tco']));
+
+        $this->getNewTicketCost(
+            [
+                'tickets_id' => $ticket->getID(),
+                'cost_material' => 10.
+            ]
+        );
+        $computer->getFromDB($computer->getID());
+        $this->assertSame(10., floatval($computer->fields['ticket_tco']));
+
+        $ticket2 = $this->getNewTicket();
+        $this->getNewItemTicket(
+            [
+                'tickets_id' => $ticket2->getID(),
+                'itemtype' => 'Computer',
+                'items_id' => $computer->getID(),
+            ]
+        );
+        $this->getNewTicketCost(
+            [
+                'tickets_id' => $ticket2->getID(),
+                'cost_fixed' => 10.,
+                'cost_material' => 80.
+            ]
+        );
+        $computer->getFromDB($computer->getID());
+        $this->assertSame(100., floatval($computer->fields['ticket_tco']));
+    }
+}
diff --git a/src/Item_Ticket.php b/src/Item_Ticket.php
index 7c07b7f6ec6..9954145b187 100644
--- a/src/Item_Ticket.php
+++ b/src/Item_Ticket.php
@@ -107,6 +107,8 @@ public function post_addItem()
         }
 
         $ticket->update($input);
+        $ticket_cost = new TicketCost();
+        $ticket_cost->updateTCOItem($this->fields['itemtype'], $this->fields['items_id']);
         parent::post_addItem();
     }
 
@@ -123,7 +125,8 @@ public function post_purgeItem()
             $input['_forcenotif'] = true;
         }
         $ticket->update($input);
-
+        $ticket_cost = new TicketCost();
+        $ticket_cost->updateTCOItem($this->fields['itemtype'], $this->fields['items_id']);
         parent::post_purgeItem();
     }
 
diff --git a/src/TicketCost.php b/src/TicketCost.php
index 4a1cc3740cd..43a593a1052 100644
--- a/src/TicketCost.php
+++ b/src/TicketCost.php
@@ -45,4 +45,49 @@ class TicketCost extends CommonITILCost
     public static $items_id  = 'tickets_id';
 
     public static $rightname        = 'ticketcost';
+
+    public function post_updateItem($history = true)
+    {
+        parent::post_updateItem($history);
+
+        $this->verifTCOItem();
+    }
+
+    public function post_addItem()
+    {
+        parent::post_addItem();
+
+        $this->verifTCOItem();
+    }
+
+    public function post_purgeItem()
+    {
+        parent::post_purgeItem();
+
+        $this->verifTCOItem();
+    }
+
+    private function verifTCOItem(): void
+    {
+        if ($this->fields['tickets_id']) {
+            $item_ticket = new Item_Ticket();
+            $item_tickets = $item_ticket->find([
+                'tickets_id' => $this->fields['tickets_id']
+            ]);
+            foreach ($item_tickets as $it) {
+                $this->updateTCOItem($it['itemtype'], $it['items_id']);
+            }
+        }
+    }
+
+    public function updateTCOItem(string $itemtype, int $items_id): void
+    {
+        $item = getItemForItemtype($itemtype);
+        if ($item && $item->getFromDB($items_id)) {
+            $item->update([
+                'id' => $items_id,
+                'ticket_tco' => Ticket::computeTco($item)
+            ]);
+        }
+    }
 }