diff --git a/addons/project/models/project.py b/addons/project/models/project.py
index 8da3d975fa3..6be03f4c4c9 100644
--- a/addons/project/models/project.py
+++ b/addons/project/models/project.py
@@ -26,7 +26,6 @@ PROJECT_TASK_READABLE_FIELDS = {
     'project_id',
     'display_project_id',
     'color',
-    'commercial_partner_id',
     'allow_subtasks',
     'subtask_count',
     'is_private',
@@ -314,7 +313,6 @@ class Project(models.Model):
         help="If the active field is set to False, it will allow you to hide the project without removing it.")
     sequence = fields.Integer(default=10)
     partner_id = fields.Many2one('res.partner', string='Customer', auto_join=True, tracking=True, check_company=True)
-    commercial_partner_id = fields.Many2one(related="partner_id.commercial_partner_id")
     company_id = fields.Many2one('res.company', string='Company', required=True, default=lambda self: self.env.company)
     currency_id = fields.Many2one('res.currency', related="company_id.currency_id", string="Currency", readonly=True)
     analytic_account_id = fields.Many2one('account.analytic.account', string="Analytic Account", copy=False, ondelete='set null',
@@ -1189,7 +1187,6 @@ class Task(models.Model):
         string='Customer', recursive=True, tracking=True,
         compute='_compute_partner_id', store=True, readonly=False,
         domain="['|', ('company_id', '=', False), ('company_id', '=', company_id)]")
-    commercial_partner_id = fields.Many2one(related='partner_id.commercial_partner_id')
     partner_phone = fields.Char(
         compute='_compute_partner_phone', inverse='_inverse_partner_phone',
         string="Phone", readonly=False, store=True, copy=False)
diff --git a/addons/project/views/project_views.xml b/addons/project/views/project_views.xml
index 82d4c07b249..a1790bb544c 100644
--- a/addons/project/views/project_views.xml
+++ b/addons/project/views/project_views.xml
@@ -755,7 +755,6 @@
                 >
                     <field name="display_name"/>
                     <field name="partner_id"/>
-                    <field name="commercial_partner_id"/>
                     <field name="color"/>
                     <field name="task_count"/>
                     <field name="milestone_count_reached"/>
diff --git a/addons/sale_project/models/project.py b/addons/sale_project/models/project.py
index a7c4b5c846c..4152c20aaae 100755
--- a/addons/sale_project/models/project.py
+++ b/addons/sale_project/models/project.py
@@ -587,7 +587,7 @@ class ProjectTask(models.Model):
     def SELF_READABLE_FIELDS(self):
         return super().SELF_READABLE_FIELDS | {'allow_billable', 'sale_order_id', 'sale_line_id', 'display_sale_order_button'}
 
-    @api.depends('sale_line_id', 'project_id', 'commercial_partner_id', 'allow_billable')
+    @api.depends('sale_line_id', 'project_id', 'partner_id.commercial_partner_id', 'allow_billable')
     def _compute_sale_order_id(self):
         for task in self:
             if not task.allow_billable:
@@ -598,13 +598,13 @@ class ProjectTask(models.Model):
                 sale_order_id = task.sale_line_id.sudo().order_id
             elif task.project_id.sale_order_id:
                 sale_order_id = task.project_id.sale_order_id
-            if task.commercial_partner_id != sale_order_id.partner_id.commercial_partner_id:
+            if task.partner_id.commercial_partner_id != sale_order_id.partner_id.commercial_partner_id:
                 sale_order_id = False
             if sale_order_id and not task.partner_id:
                 task.partner_id = sale_order_id.partner_id
             task.sale_order_id = sale_order_id
 
-    @api.depends('commercial_partner_id', 'sale_line_id.order_partner_id', 'parent_id.sale_line_id', 'project_id.sale_line_id', 'milestone_id.sale_line_id', 'allow_billable')
+    @api.depends('partner_id.commercial_partner_id', 'sale_line_id.order_partner_id', 'parent_id.sale_line_id', 'project_id.sale_line_id', 'milestone_id.sale_line_id', 'allow_billable')
     def _compute_sale_line(self):
         for task in self:
             if not task.allow_billable:
diff --git a/addons/sale_project/views/project_sharing_views.xml b/addons/sale_project/views/project_sharing_views.xml
index 59fe6e587fe..d7dd046b4ca 100644
--- a/addons/sale_project/views/project_sharing_views.xml
+++ b/addons/sale_project/views/project_sharing_views.xml
@@ -19,7 +19,6 @@
                 <attribute name="context">{'res_partner_search_mode': 'customer'}</attribute>
             </xpath>
             <xpath expr="//field[@name='partner_id']" position="after">
-                <field name="commercial_partner_id" invisible="1" />
                 <field name="sale_line_id" string="Sales Order Item" attrs="{'invisible': [('partner_id', '=', False)]}" options='{"no_open": True}' readonly="1" context="{'create': False, 'edit': False, 'delete': False}"/>
             </xpath>
         </field>
diff --git a/addons/sale_project/views/project_task_views.xml b/addons/sale_project/views/project_task_views.xml
index e17470c7695..40431068ef4 100644
--- a/addons/sale_project/views/project_task_views.xml
+++ b/addons/sale_project/views/project_task_views.xml
@@ -85,7 +85,6 @@
                 <field name="sale_order_id" attrs="{'invisible': True}" groups="sales_team.group_sale_salesman"/>
                 <field name="sale_line_id" groups="!sales_team.group_sale_salesman" string="Sales Order Item" options='{"no_open": True}' readonly="1" context="{'create': False, 'edit': False, 'delete': False}" attrs="{'invisible': ['|', ('allow_billable', '=', False), ('project_id', '=', False)]}"/>
                 <field name="sale_line_id" groups="sales_team.group_sale_salesman" string="Sales Order Item" options='{"no_create": True}' readonly="0" context="{'create': False, 'edit': False, 'delete': False, 'with_price_unit': True}" placeholder="Non-billable" attrs="{'invisible': ['|', ('allow_billable', '=', False), ('project_id', '=', False)]}"/>
-                <field name="commercial_partner_id" invisible="1" />
                 <field name="allow_billable" invisible="1"/>
             </xpath>
         </field>
diff --git a/addons/sale_timesheet/models/account.py b/addons/sale_timesheet/models/account.py
index 104e1d7901d..c9d62e277f9 100644
--- a/addons/sale_timesheet/models/account.py
+++ b/addons/sale_timesheet/models/account.py
@@ -37,10 +37,10 @@ class AccountAnalyticLine(models.Model):
     is_so_line_edited = fields.Boolean("Is Sales Order Item Manually Edited")
     allow_billable = fields.Boolean(related="project_id.allow_billable")
 
-    @api.depends('project_id.commercial_partner_id', 'task_id.commercial_partner_id')
+    @api.depends('project_id.partner_id.commercial_partner_id', 'task_id.partner_id.commercial_partner_id')
     def _compute_commercial_partner(self):
         for timesheet in self:
-            timesheet.commercial_partner_id = timesheet.task_id.commercial_partner_id or timesheet.project_id.commercial_partner_id
+            timesheet.commercial_partner_id = timesheet.task_id.partner_id.commercial_partner_id or timesheet.project_id.partner_id.commercial_partner_id
 
     @api.depends('so_line.product_id', 'project_id', 'amount')
     def _compute_timesheet_invoice_type(self):
@@ -115,7 +115,7 @@ class AccountAnalyticLine(models.Model):
                 map_entry = self.project_id.sale_line_employee_ids.filtered(
                     lambda map_entry:
                         map_entry.employee_id == self.employee_id
-                        and map_entry.sale_line_id.order_partner_id.commercial_partner_id == self.task_id.commercial_partner_id
+                        and map_entry.sale_line_id.order_partner_id.commercial_partner_id == self.task_id.partner_id.commercial_partner_id
                 )
                 if map_entry:
                     return map_entry.sale_line_id
diff --git a/addons/sale_timesheet/models/project.py b/addons/sale_timesheet/models/project.py
index de180f748cd..a0f56e7895a 100644
--- a/addons/sale_timesheet/models/project.py
+++ b/addons/sale_timesheet/models/project.py
@@ -555,7 +555,7 @@ class ProjectTask(models.Model):
         for task in self:
             task.analytic_account_active = task.analytic_account_active or task.so_analytic_account_id.active
 
-    @api.depends('commercial_partner_id', 'sale_line_id.order_partner_id', 'parent_id.sale_line_id', 'project_id.sale_line_id', 'allow_billable')
+    @api.depends('partner_id.commercial_partner_id', 'sale_line_id.order_partner_id', 'parent_id.sale_line_id', 'project_id.sale_line_id', 'allow_billable')
     def _compute_sale_line(self):
         super()._compute_sale_line()
         for task in self:
@@ -575,10 +575,10 @@ class ProjectTask(models.Model):
     def _get_last_sol_of_customer(self):
         # Get the last SOL made for the customer in the current task where we need to compute
         self.ensure_one()
-        if not self.commercial_partner_id or not self.allow_billable:
+        if not self.partner_id.commercial_partner_id or not self.allow_billable:
             return False
-        domain = [('company_id', '=', self.company_id.id), ('is_service', '=', True), ('order_partner_id', 'child_of', self.commercial_partner_id.id), ('is_expense', '=', False), ('state', 'in', ['sale', 'done']), ('remaining_hours', '>', 0)]
-        if self.project_id.pricing_type != 'task_rate' and self.project_sale_order_id and self.commercial_partner_id == self.project_id.partner_id.commercial_partner_id:
+        domain = [('company_id', '=', self.company_id.id), ('is_service', '=', True), ('order_partner_id', 'child_of', self.partner_id.commercial_partner_id.id), ('is_expense', '=', False), ('state', 'in', ['sale', 'done']), ('remaining_hours', '>', 0)]
+        if self.project_id.pricing_type != 'task_rate' and self.project_sale_order_id and self.partner_id.commercial_partner_id == self.project_id.partner_id.commercial_partner_id:
             domain.append(('order_id', '=?', self.project_sale_order_id.id))
         return self.env['sale.order.line'].search(domain, limit=1)
 
diff --git a/addons/sale_timesheet/views/project_task_views.xml b/addons/sale_timesheet/views/project_task_views.xml
index cd709fff54f..e29058bfe20 100644
--- a/addons/sale_timesheet/views/project_task_views.xml
+++ b/addons/sale_timesheet/views/project_task_views.xml
@@ -138,12 +138,12 @@
                     <field name="so_line" groups="!sales_team.group_sale_salesman"
                         attrs="{'column_invisible': [('parent.allow_billable', '=', False)]}"
                         context="{'with_remaining_hours': True, 'with_price_unit': True}" options="{'no_create': True, 'no_open': True}"
-                        domain="[('is_service', '=', True), ('order_partner_id', 'child_of', parent.commercial_partner_id), ('is_expense', '=', False), ('state', 'in', ['sale', 'done'])]"
+                        domain="[('is_service', '=', True), ('order_partner_id', 'child_of', parent.partner_id), ('is_expense', '=', False), ('state', 'in', ['sale', 'done'])]"
                         optional="hide"/>
                     <field name="so_line" groups="sales_team.group_sale_salesman"
                         attrs="{'column_invisible': [('parent.allow_billable', '=', False)]}"
                         context="{'with_remaining_hours': True, 'with_price_unit': True}" options="{'no_create': True}"
-                        domain="[('is_service', '=', True), ('order_partner_id', 'child_of', parent.commercial_partner_id), ('is_expense', '=', False), ('state', 'in', ['sale', 'done'])]"
+                        domain="[('is_service', '=', True), ('order_partner_id', 'child_of', parent.partner_id), ('is_expense', '=', False), ('state', 'in', ['sale', 'done'])]"
                         optional="hide"/>
                 </xpath>
                 <xpath expr="//field[@name='remaining_hours']" position="after">