diff --git a/addons/hr_timesheet/controllers/portal.py b/addons/hr_timesheet/controllers/portal.py
index 30e61e4f2ec..93d54d12492 100644
--- a/addons/hr_timesheet/controllers/portal.py
+++ b/addons/hr_timesheet/controllers/portal.py
@@ -33,8 +33,8 @@ class TimesheetCustomerPortal(CustomerPortal):
             'name': {'input': 'name', 'label': _('Search in Description')},
         }
 
-    def _task_get_searchbar_sortings(self, milestones_allowed):
-        values = super()._task_get_searchbar_sortings(milestones_allowed)
+    def _task_get_searchbar_sortings(self, milestones_allowed, project=False):
+        values = super()._task_get_searchbar_sortings(milestones_allowed, project)
         values['progress'] = {'label': _('Progress'), 'order': 'progress asc', 'sequence': 10}
         return values
 
diff --git a/addons/project/controllers/portal.py b/addons/project/controllers/portal.py
index 04a52235b6f..b3fd5cb1932 100644
--- a/addons/project/controllers/portal.py
+++ b/addons/project/controllers/portal.py
@@ -33,7 +33,7 @@ class ProjectCustomerPortal(CustomerPortal):
         domain = [('project_id', '=', project.id)]
         # pager
         url = "/my/projects/%s" % project.id
-        values = self._prepare_tasks_values(page, date_begin, date_end, sortby, search, search_in, groupby, url, domain, su=bool(access_token))
+        values = self._prepare_tasks_values(page, date_begin, date_end, sortby, search, search_in, groupby, url, domain, su=bool(access_token), project=project)
         pager = portal_pager(**values['pager'])
 
         values.update(
@@ -264,11 +264,10 @@ class ProjectCustomerPortal(CustomerPortal):
 
         return values
 
-    def _task_get_searchbar_sortings(self, milestones_allowed):
+    def _task_get_searchbar_sortings(self, milestones_allowed, project=False):
         values = {
             'date': {'label': _('Newest'), 'order': 'create_date desc', 'sequence': 1},
             'name': {'label': _('Title'), 'order': 'name', 'sequence': 2},
-            'project': {'label': _('Project'), 'order': 'project_id, stage_id', 'sequence': 3},
             'users': {'label': _('Assignees'), 'order': 'user_ids', 'sequence': 4},
             'stage': {'label': _('Stage'), 'order': 'stage_id, project_id', 'sequence': 5},
             'status': {'label': _('Status'), 'order': 'state', 'sequence': 6},
@@ -276,19 +275,22 @@ class ProjectCustomerPortal(CustomerPortal):
             'date_deadline': {'label': _('Deadline'), 'order': 'date_deadline asc', 'sequence': 9},
             'update': {'label': _('Last Stage Update'), 'order': 'date_last_stage_update desc', 'sequence': 11},
         }
+        if not project:
+            values['project'] = {'label': _('Project'), 'order': 'project_id, stage_id', 'sequence': 3}
         if milestones_allowed:
             values['milestone'] = {'label': _('Milestone'), 'order': 'milestone_id', 'sequence': 7}
         return values
 
-    def _task_get_searchbar_groupby(self, milestones_allowed):
+    def _task_get_searchbar_groupby(self, milestones_allowed, project=False):
         values = {
             'none': {'input': 'none', 'label': _('None'), 'order': 1},
-            'project': {'input': 'project', 'label': _('Project'), 'order': 2},
             'stage': {'input': 'stage', 'label': _('Stage'), 'order': 4},
             'status': {'input': 'status', 'label': _('Status'), 'order': 5},
             'priority': {'input': 'priority', 'label': _('Priority'), 'order': 7},
             'customer': {'input': 'customer', 'label': _('Customer'), 'order': 10},
         }
+        if not project:
+            values['project'] = {'input': 'project', 'label': _('Project'), 'order': 2}
         if milestones_allowed:
             values['milestone'] = {'input': 'milestone', 'label': _('Milestone'), 'order': 6}
         return dict(sorted(values.items(), key=lambda item: item[1]["order"]))
@@ -310,18 +312,20 @@ class ProjectCustomerPortal(CustomerPortal):
             return order
         return '%s, %s' % (field_name, order)
 
-    def _task_get_searchbar_inputs(self, milestones_allowed):
+    def _task_get_searchbar_inputs(self, milestones_allowed, project=False):
         values = {
             'all': {'input': 'all', 'label': _('Search in All'), 'order': 1},
             'content': {'input': 'content', 'label': Markup(_('Search <span class="nolabel"> (in Content)</span>')), 'order': 1},
             'ref': {'input': 'ref', 'label': _('Search in Ref'), 'order': 1},
-            'project': {'input': 'project', 'label': _('Search in Project'), 'order': 2},
             'users': {'input': 'users', 'label': _('Search in Assignees'), 'order': 3},
             'stage': {'input': 'stage', 'label': _('Search in Stages'), 'order': 4},
             'status': {'input': 'status', 'label': _('Search in Status'), 'order': 5},
             'priority': {'input': 'priority', 'label': _('Search in Priority'), 'order': 7},
+            'customer': {'input': 'customer', 'label': _('Search in Customer'), 'order': 10},
             'message': {'input': 'message', 'label': _('Search in Messages'), 'order': 11},
         }
+        if not project:
+            values['project'] = {'input': 'project', 'label': _('Search in Project'), 'order': 2}
         if milestones_allowed:
             values['milestone'] = {'input': 'milestone', 'label': _('Search in Milestone'), 'order': 6}
 
@@ -354,16 +358,16 @@ class ProjectCustomerPortal(CustomerPortal):
             search_domain.append([('state', 'ilike', state_dict.get(search, search))])
         return OR(search_domain)
 
-    def _prepare_tasks_values(self, page, date_begin, date_end, sortby, search, search_in, groupby, url="/my/tasks", domain=None, su=False):
+    def _prepare_tasks_values(self, page, date_begin, date_end, sortby, search, search_in, groupby, url="/my/tasks", domain=None, su=False, project=False):
         values = self._prepare_portal_layout_values()
 
         Task = request.env['project.task']
         milestone_domain = AND([domain, [('allow_milestones', '=', 'True')]])
         milestones_allowed = Task.sudo().search_count(milestone_domain, limit=1) == 1
-        searchbar_sortings = dict(sorted(self._task_get_searchbar_sortings(milestones_allowed).items(),
+        searchbar_sortings = dict(sorted(self._task_get_searchbar_sortings(milestones_allowed, project).items(),
                                          key=lambda item: item[1]["sequence"]))
-        searchbar_inputs = self._task_get_searchbar_inputs(milestones_allowed)
-        searchbar_groupby = self._task_get_searchbar_groupby(milestones_allowed)
+        searchbar_inputs = self._task_get_searchbar_inputs(milestones_allowed, project)
+        searchbar_groupby = self._task_get_searchbar_groupby(milestones_allowed, project)
 
         if not domain:
             domain = []
@@ -379,6 +383,8 @@ class ProjectCustomerPortal(CustomerPortal):
         # default group by value
         if not groupby or (groupby == 'milestone' and not milestones_allowed):
             groupby = 'project'
+        if project:
+            groupby = 'stage'
 
         if date_begin and date_end:
             domain += [('create_date', '>', date_begin), ('create_date', '<=', date_end)]
diff --git a/addons/project/models/project_project.py b/addons/project/models/project_project.py
index 1ebd49a71c0..646aa061e50 100644
--- a/addons/project/models/project_project.py
+++ b/addons/project/models/project_project.py
@@ -771,6 +771,9 @@ class Project(models.Model):
     #  Business Methods
     # ---------------------------------------------------
 
+    def _get_hide_partner(self):
+        return False
+
     @api.model
     def _create_analytic_account_from_values(self, values):
         company = self.env['res.company'].browse(values.get('company_id')) if values.get('company_id') else self.env.company
diff --git a/addons/project/models/project_task.py b/addons/project/models/project_task.py
index a5f78e3f247..e415efd49cc 100644
--- a/addons/project/models/project_task.py
+++ b/addons/project/models/project_task.py
@@ -179,10 +179,6 @@ 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)]")
-    partner_phone = fields.Char(
-        compute='_compute_partner_phone', inverse='_inverse_partner_phone',
-        string="Phone", readonly=False, store=True, copy=False)
-    partner_city = fields.Char(related='partner_id.city', readonly=False)
     email_cc = fields.Char(help='Email addresses that were in the CC of the incoming emails from this task and that are not currently linked to an existing customer.')
     company_id = fields.Many2one(
         'res.company', string='Company', compute='_compute_company_id', store=True, readonly=False, recursive=True,
@@ -469,17 +465,6 @@ class Task(models.Model):
             for task in tasks_with_dependency:
                 task.dependent_tasks_count = dependent_tasks_count_dict.get(task.id, 0)
 
-    @api.depends('partner_id.phone')
-    def _compute_partner_phone(self):
-        for task in self:
-            if task.partner_phone != task.partner_id.phone:
-                task.partner_phone = task.partner_id.phone
-
-    def _inverse_partner_phone(self):
-        for task in self:
-            if task.partner_id and task.partner_phone != task.partner_id.phone:
-                task.partner_id.phone = task.partner_phone
-
     @api.constrains('parent_id')
     def _check_parent_id(self):
         if not self._check_recursion():
diff --git a/addons/project/models/project_task_recurrence.py b/addons/project/models/project_task_recurrence.py
index f43e1cd8e12..c20b15c994b 100644
--- a/addons/project/models/project_task_recurrence.py
+++ b/addons/project/models/project_task_recurrence.py
@@ -48,7 +48,6 @@ class ProjectTaskRecurrence(models.Model):
             'name',
             'parent_id',
             'partner_id',
-            'partner_phone',
             'planned_hours',
             'project_id',
             'project_privacy_visibility',
diff --git a/addons/project/views/project_sharing_project_task_views.xml b/addons/project/views/project_sharing_project_task_views.xml
index 3589bcbc01d..20802099d53 100644
--- a/addons/project/views/project_sharing_project_task_views.xml
+++ b/addons/project/views/project_sharing_project_task_views.xml
@@ -175,7 +175,7 @@
                             <field name="company_id" invisible="1" />
                             <field name="is_closed" invisible="1" />
                             <field name="allow_subtasks" invisible="1" />
-                            <field name="partner_id" options="{'no_open': True, 'no_create': True, 'no_edit': True}"/>
+                            <field name="partner_id" options="{'no_open': True, 'no_create': True, 'no_edit': True}" attrs="{'invisible': [('project_id', '=', False)]}"/>
                             <field name="date_deadline" attrs="{'invisible': [('is_closed', '=', True)]}"/>
                         </group>
                     </group>
@@ -198,7 +198,7 @@
                                         attrs="{'invisible': [('allow_milestones', '=', False)], 'column_invisible': [('parent.allow_milestones', '=', False)]}"
                                     />
                                     <field name="company_id" invisible="1"/>
-                                    <field name="partner_id" options="{'no_open': True, 'no_create': True, 'no_edit': True}" optional="hide"/>
+                                    <field name="partner_id" options="{'no_open': True, 'no_create': True, 'no_edit': True}" optional="hide" attrs="{'invisible': [('project_id', '=', False)]}"/>
                                     <field name="user_ids" invisible="1" />
                                     <field name="portal_user_names" string="Assignees" optional="show"/>
                                     <field name="date_deadline" attrs="{'invisible': [('is_closed', '=', True)]}" optional="show"/>
diff --git a/addons/project/views/project_task_views.xml b/addons/project/views/project_task_views.xml
index 43c3cf361b0..adb4224d562 100644
--- a/addons/project/views/project_task_views.xml
+++ b/addons/project/views/project_task_views.xml
@@ -52,7 +52,7 @@
             <field name="priority">999</field>
             <field name="arch" type="xml">
                 <field name="stage_id" position="after">
-                    <field name="project_id" string="Project" invisible="context.get('default_project_id')"/>
+                    <field name="project_id" string="Project"/>
                 </field>
                 <field name="partner_id" position="after">
                     <field name="company_id" groups="base.group_multi_company"/>
@@ -61,7 +61,7 @@
                     <filter string="My Tasks" name="my_tasks" domain="[('user_ids', 'in', uid)]"/>
                 </field>
                 <filter name="stage" position="after">
-                    <filter string="Project" name="project" context="{'group_by': 'project_id'}" invisible="context.get('default_project_id')"/>
+                    <filter string="Project" name="project" context="{'group_by': 'project_id'}"/>
                 </filter>
             </field>
         </record>
@@ -342,7 +342,6 @@
                         <group>
                             <field name="active" invisible="1"/>
                             <field name="partner_id" nolabel="0" widget="res_partner_many2one" class="o_task_customer_field" attrs="{'invisible': [('project_id', '=', False)]}"/>
-                            <field name="partner_phone" widget="phone" attrs="{'invisible': True}"/>
                             <label for="date_deadline"/>
                             <div id="date_deadline_and_recurring_task" class="d-inline-flex w-100">
                                 <field name="date_deadline" nolabel="1"/>
@@ -392,7 +391,7 @@
                                         context="{'default_project_id': project_id}"
                                         attrs="{'invisible': [('allow_milestones', '=', False)], 'column_invisible': [('parent.allow_milestones', '=', False)]}"
                                     />
-                                    <field name="partner_id" optional="hide"/>
+                                    <field name="partner_id" optional="hide" widget="res_partner_many2one" attrs="{'invisible': [('project_id', '=', False)]}"/>
                                     <field name="user_ids" widget="many2many_avatar_user" optional="show" domain="[('share', '=', False), ('active', '=', True)]"/>
                                     <field name="company_id" groups="base.group_multi_company" optional="hide"/>
                                     <field name="company_id" invisible="1"/>
@@ -427,7 +426,7 @@
                                         context="{'default_project_id': project_id}"
                                         attrs="{'invisible': [('allow_milestones', '=', False)], 'column_invisible': [('parent.allow_milestones', '=', False)]}"
                                     />
-                                    <field name="partner_id" optional="hide"/>
+                                    <field name="partner_id" optional="hide" widget="res_partner_many2one" attrs="{'invisible': [('project_id', '=', False)]}"/>
                                     <field name="parent_id" optional="hide" attrs="{'invisible': [('allow_subtasks', '=', False)]}" groups="base.group_no_one"/>
                                     <field name="user_ids" widget="many2many_avatar_user" optional="show" domain="[('share', '=', False), ('active', '=', True)]"/>
                                     <field name="company_id" optional="hide" groups="base.group_multi_company" />
@@ -625,7 +624,7 @@
                     <field name="name" string="Title" widget="name_with_subtask_count"/>
                     <field name="project_id" widget="project_private_task" optional="show" readonly="1" options="{'no_open': 1}" invisible="context.get('default_project_id')"/>
                     <field name="milestone_id" attrs="{'invisible': [('allow_milestones', '=', False)]}" context="{'default_project_id': project_id}" groups="project.group_project_milestone" optional="hide"/>
-                    <field name="partner_id" optional="hide" widget="res_partner_many2one" context="{'res_partner_search_mode': 'customer'}"/>
+                    <field name="partner_id" optional="hide" widget="res_partner_many2one" context="{'res_partner_search_mode': 'customer'}" attrs="{'invisible': [('project_id', '=', False)]}"/>
                     <field name="user_ids" optional="show" widget="many2many_avatar_user" domain="[('share', '=', False), ('active', '=', True)]"/>
                     <field name="company_id" groups="base.group_multi_company" optional="show" invisible="context.get('default_project_id')"/>
                     <field name="date_deadline" optional="hide" widget="remaining_days" attrs="{'invisible': [('is_closed', '=', True)]}"/>
diff --git a/addons/sale_project/__init__.py b/addons/sale_project/__init__.py
index 3226df762b3..852082dcf71 100644
--- a/addons/sale_project/__init__.py
+++ b/addons/sale_project/__init__.py
@@ -4,3 +4,7 @@
 from . import models
 from . import controllers
 from . import report
+
+def _set_allow_billable_in_project(env):
+    projects = env['project.project'].search([('partner_id', '!=', False), ('allow_billable', '=', False)])
+    projects.allow_billable = True
diff --git a/addons/sale_project/__manifest__.py b/addons/sale_project/__manifest__.py
index 1fd54153e9c..f69e0bd5ccb 100644
--- a/addons/sale_project/__manifest__.py
+++ b/addons/sale_project/__manifest__.py
@@ -26,5 +26,6 @@ This module allows to generate a project/task from sales orders.
             'sale_project/static/src/components/project_right_side_panel/**/*',
         ],
     },
+    'post_init_hook': '_set_allow_billable_in_project',
     'license': 'LGPL-3',
 }
diff --git a/addons/sale_project/controllers/portal.py b/addons/sale_project/controllers/portal.py
index b621011cbdf..43cecdfb4a0 100644
--- a/addons/sale_project/controllers/portal.py
+++ b/addons/sale_project/controllers/portal.py
@@ -9,10 +9,13 @@ from odoo.addons.project.controllers.portal import ProjectCustomerPortal
 
 class SaleProjectCustomerPortal(ProjectCustomerPortal):
 
-    def _task_get_searchbar_groupby(self, milestones_allowed):
-        values = super()._task_get_searchbar_groupby(milestones_allowed)
-        values['sale_order'] = {'input': 'sale_order', 'label': _lt('Sales Order'), 'order': 8}
-        values['sale_line'] = {'input': 'sale_line', 'label': _lt('Sales Order Item'), 'order': 9}
+    def _task_get_searchbar_groupby(self, milestones_allowed, project=False):
+        values = super()._task_get_searchbar_groupby(milestones_allowed, project)
+        if project and not project.sudo()._get_hide_partner():
+            del values['customer']
+        if not project or project.sudo().allow_billable:
+            values['sale_order'] = {'input': 'sale_order', 'label': _lt('Sales Order'), 'order': 8}
+            values['sale_line'] = {'input': 'sale_line', 'label': _lt('Sales Order Item'), 'order': 9}
         return dict(sorted(values.items(), key=lambda item: item[1]["order"]))
 
     def _task_get_groupby_mapping(self):
@@ -20,11 +23,14 @@ class SaleProjectCustomerPortal(ProjectCustomerPortal):
         groupby_mapping.update(sale_order='sale_order_id', sale_line='sale_line_id')
         return groupby_mapping
 
-    def _task_get_searchbar_inputs(self, milestones_allowed):
-        values = super()._task_get_searchbar_inputs(milestones_allowed)
-        values['sale_order'] = {'input': 'sale_order', 'label': _lt('Search in Sales Order'), 'order': 8}
-        values['sale_line'] = {'input': 'sale_line', 'label': _lt('Search in Sales Order Item'), 'order': 9}
-        values['invoice'] = {'input': 'invoice', 'label': _lt('Search in Invoice'), 'order': 10}
+    def _task_get_searchbar_inputs(self, milestones_allowed, project=False):
+        values = super()._task_get_searchbar_inputs(milestones_allowed, project)
+        if project and not project.sudo()._get_hide_partner():
+            del values['customer']
+        if not project or project.sudo().allow_billable:
+            values['sale_order'] = {'input': 'sale_order', 'label': _lt('Search in Sales Order'), 'order': 8}
+            values['sale_line'] = {'input': 'sale_line', 'label': _lt('Search in Sales Order Item'), 'order': 9}
+            values['invoice'] = {'input': 'invoice', 'label': _lt('Search in Invoice'), 'order': 10}
         return dict(sorted(values.items(), key=lambda item: item[1]["order"]))
 
     def _task_get_search_domain(self, search_in, search):
diff --git a/addons/sale_project/models/project.py b/addons/sale_project/models/project.py
index 66d6be36df9..40a64676efd 100755
--- a/addons/sale_project/models/project.py
+++ b/addons/sale_project/models/project.py
@@ -27,6 +27,7 @@ class Project(models.Model):
     has_any_so_with_nothing_to_invoice = fields.Boolean('Has a SO with an invoice status of No', compute='_compute_has_any_so_with_nothing_to_invoice')
     invoice_count = fields.Integer(related='analytic_account_id.invoice_count', groups='account.group_account_readonly')
     vendor_bill_count = fields.Integer(related='analytic_account_id.vendor_bill_count', groups='account.group_account_readonly')
+    partner_id = fields.Many2one(compute="_compute_partner_id", store=True, readonly=False)
 
     @api.model
     def _map_tasks_default_valeus(self, task, project):
@@ -34,6 +35,10 @@ class Project(models.Model):
         defaults['sale_line_id'] = False
         return defaults
 
+    @api.depends('allow_billable')
+    def _compute_partner_id(self):
+        self.filtered(lambda project: not project.allow_billable).partner_id = False
+
     @api.depends('partner_id')
     def _compute_sale_line_id(self):
         self.filtered(
@@ -537,6 +542,18 @@ class Project(models.Model):
             })
         return buttons
 
+    # ---------------------------------------------------
+    # Actions
+    # ---------------------------------------------------
+
+    def _get_hide_partner(self):
+        return not self.allow_billable
+
+    def action_view_tasks(self):
+        action = super().action_view_tasks()
+        action['context']['hide_partner'] = self._get_hide_partner()
+        return action
+
     def action_open_project_vendor_bills(self):
         query = self.env['account.move.line']._search([('move_id.move_type', 'in', ['in_invoice', 'in_refund'])])
         query.add_where('analytic_distribution ? %s', [str(self.analytic_account_id.id)])
@@ -562,6 +579,7 @@ class Project(models.Model):
         action = super().action_project_sharing()
         action['context'].update({
             'sale_show_partner_name': True,
+            'hide_partner': self._get_hide_partner(),
         })
         return action
 
@@ -605,6 +623,12 @@ class ProjectTask(models.Model):
                 task.partner_id = sale_order_id.partner_id
             task.sale_order_id = sale_order_id
 
+    @api.depends('allow_billable')
+    def _compute_partner_id(self):
+        billable_task = self.filtered('allow_billable')
+        (self - billable_task).partner_id = False
+        super(ProjectTask, billable_task)._compute_partner_id()
+
     @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:
diff --git a/addons/sale_project/tests/test_child_tasks.py b/addons/sale_project/tests/test_child_tasks.py
index 6f91ae99da8..8e86663bb4e 100644
--- a/addons/sale_project/tests/test_child_tasks.py
+++ b/addons/sale_project/tests/test_child_tasks.py
@@ -47,7 +47,7 @@ class TestNestedTaskUpdate(TransactionCase):
         self.assertEqual(parent.partner_id, self.project.partner_id, "The partner set on the parent task should the one set on the project linked")
         self.assertFalse(child.project_id, "The project set on the subtask should be False by default")
         self.assertFalse(child.allow_billable, "The subtask should not be billable as it is parent task since no project is set")
-        self.assertEqual(child.partner_id, parent.partner_id, "The partner set on the subtask should be the one of its parent task")
+        self.assertFalse(child.partner_id, "Subtask with no project should not have partner")
 
     def test_creating_subtask_user_id_on_parent_dont_go_on_child(self):
         parent = self.env['project.task'].create({'name': 'parent', 'user_ids': [(4, self.user.id)]})
@@ -56,12 +56,12 @@ class TestNestedTaskUpdate(TransactionCase):
 
     def test_creating_subtask_partner_id_on_parent_goes_on_child(self):
         parent = self.env['project.task'].create({'name': 'parent', 'partner_id': self.user.partner_id.id, 'project_id': self.project.id})
-        child = self.env['project.task'].create({'name': 'child', 'parent_id': parent.id})
+        child = self.env['project.task'].create({'name': 'child', 'parent_id': parent.id, 'project_id': self.project.id})
         child._compute_partner_id()  # the compute will be triggered since the user set the parent_id.
         self.assertEqual(child.partner_id, self.user.partner_id)
 
         # Another case, it is the parent as a default value
-        child = self.env['project.task'].with_context(default_parent_id=parent.id).create({'name': 'child'})
+        child = self.env['project.task'].with_context(default_parent_id=parent.id, default_project_id=self.project.id).create({'name': 'child'})
         self.assertEqual(child.partner_id, self.user.partner_id)
 
     def test_creating_subtask_sale_line_id_on_parent_goes_on_child_if_same_partner_in_values(self):
@@ -157,10 +157,10 @@ class TestNestedTaskUpdate(TransactionCase):
         self.assertFalse(child.user_ids)
 
     def test_linking_partner_id_on_parent_write_on_child(self):
-        parent = self.env['project.task'].create({'name': 'parent', 'partner_id': self.user.partner_id.id})
+        parent = self.env['project.task'].create({'name': 'parent', 'partner_id': self.user.partner_id.id, 'project_id': self.project.id})
         child = self.env['project.task'].create({'name': 'child', 'partner_id': False})
         self.assertFalse(child.partner_id)
-        child.write({'parent_id': parent.id})
+        child.write({'parent_id': parent.id, 'project_id': self.project.id})
         self.assertEqual(child.partner_id, self.user.partner_id)
 
     def test_linking_sale_line_id_on_parent_write_on_child_if_same_partner(self):
diff --git a/addons/sale_project/views/project_sharing_views.xml b/addons/sale_project/views/project_sharing_views.xml
index d7dd046b4ca..b78261ce644 100644
--- a/addons/sale_project/views/project_sharing_views.xml
+++ b/addons/sale_project/views/project_sharing_views.xml
@@ -9,6 +9,7 @@
         <field name="arch" type="xml">
             <div name="button_box" position="inside">
                 <field name="display_sale_order_button" invisible="1"/>
+                <field name="allow_billable" invisible="1"/>
                 <button class="oe_stat_button"
                         type="object" name="action_project_sharing_view_so" icon="fa-dollar"
                         attrs="{'invisible': [('display_sale_order_button', '=', False)]}"
@@ -17,10 +18,17 @@
             <xpath expr="//field[@name='partner_id']" position="attributes">
                 <attribute name="options">{'no_open': True, 'no_create': True, 'no_edit': True}</attribute>
                 <attribute name="context">{'res_partner_search_mode': 'customer'}</attribute>
+                <attribute name="attrs">{'invisible': [('allow_billable', '=', False)]}</attribute>
             </xpath>
             <xpath expr="//field[@name='partner_id']" position="after">
                 <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>
+            <xpath expr="//field[@name='child_ids']/tree/field[@name='partner_id']" position="after">
+                <field name="allow_billable"/>
+            </xpath>
+            <xpath expr="//field[@name='child_ids']/tree/field[@name='partner_id']" position="attributes">
+                <attribute name="attrs">{'column_invisible': [('parent.allow_billable', '=', False)], 'invisible': [('allow_billable', '=', False)]}</attribute>
+            </xpath>
         </field>
     </record>
 
diff --git a/addons/sale_project/views/project_task_views.xml b/addons/sale_project/views/project_task_views.xml
index 40431068ef4..0ea7e86c46c 100644
--- a/addons/sale_project/views/project_task_views.xml
+++ b/addons/sale_project/views/project_task_views.xml
@@ -36,6 +36,10 @@
         <field name="arch" type="xml">
             <xpath expr="//field[@name='partner_id']" position="after">
                 <field name="sale_line_id" optional="hide" readonly="1"/>
+                <field name="allow_billable" invisible="1"/>
+            </xpath>
+            <xpath expr="//field[@name='partner_id']" position="attributes">
+                <attribute name="attrs">{'invisible': [('allow_billable', '=', False)]}</attribute>
             </xpath>
         </field>
     </record>
@@ -52,6 +56,7 @@
             <xpath expr="//field[@name='partner_id']" position="attributes">
                 <attribute name="options">{'always_reload': True}</attribute>
                 <attribute name="context">{'res_partner_search_mode': 'customer'}</attribute>
+                <attribute name="attrs">{'invisible': [('allow_billable', '=', False)]}</attribute>
             </xpath>
             <xpath expr="//group[@name='group_time_managment']" position="after">
                  <group name="group_sales_invoicing" string="Sales &amp; Invoicing" col="1" class="row mt16 o_settings_container col-lg-6">
@@ -80,13 +85,41 @@
             <xpath expr="//field[@name='partner_id']" position="attributes">
                 <attribute name="options">{'always_reload': True}</attribute>
                 <attribute name="context">{'res_partner_search_mode': 'customer'}</attribute>
+                <attribute name="attrs">{'invisible': [('allow_billable', '=', False)]}</attribute>
             </xpath>
-            <xpath expr="//field[@name='partner_phone']" position="after">
+            <xpath expr="//field[@name='partner_id']" position="after">
                 <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="allow_billable" invisible="1"/>
             </xpath>
+            <xpath expr="//field[@name='child_ids']/tree/field[@name='partner_id']" position="after">
+                <field name="allow_billable" invisible="1"/>
+            </xpath>
+            <xpath expr="//field[@name='child_ids']/tree/field[@name='partner_id']" position="attributes">
+                <attribute name="attrs">{'column_invisible': [('parent.allow_billable', '=', False)], 'invisible': [('allow_billable', '=', False)]}</attribute>
+            </xpath>
+            <xpath expr="//field[@name='depend_on_ids']/tree/field[@name='partner_id']" position="after">
+                <field name="allow_billable" invisible="1"/>
+            </xpath>
+            <xpath expr="//field[@name='depend_on_ids']/tree/field[@name='partner_id']" position="attributes">
+                <attribute name="attrs">{'column_invisible': [('parent.allow_billable', '=', False)], 'invisible': [('allow_billable', '=', False)]}</attribute>
+            </xpath>
+        </field>
+    </record>
+
+    <record id="project_task_view_tree_main_base" model="ir.ui.view">
+        <field name="name">project.task.main.tree.inherit</field>
+        <field name="model">project.task</field>
+        <field name="inherit_id" ref="project.project_task_view_tree_main_base"/>
+        <field name="arch" type="xml">
+            <field name="partner_id" position="after">
+                <field name="allow_billable" invisible="1"/>
+            </field>
+            <field name="partner_id" position="attributes">
+                <attribute name="attrs">{'invisible': [('allow_billable', '=', False)]}</attribute>
+                <attribute name="invisible">context.get('hide_partner')</attribute>
+            </field>
         </field>
     </record>
 
@@ -109,6 +142,12 @@
             <field name="partner_id" position="after">
                 <field name="sale_order_id" filter_domain="['|', ('sale_order_id', 'ilike', self), ('sale_line_id', 'ilike', self)]"/>
             </field>
+            <field name="partner_id" position="attributes">
+                <attribute name="invisible">context.get('hide_partner')</attribute>
+            </field>
+            <filter name="customer" position="attributes">
+                <attribute name="invisible">context.get('hide_partner')</attribute>
+            </filter>
         </field>
     </record>
 
diff --git a/addons/sale_timesheet/models/project.py b/addons/sale_timesheet/models/project.py
index 6f53bc8b076..c84fcde77d5 100644
--- a/addons/sale_timesheet/models/project.py
+++ b/addons/sale_timesheet/models/project.py
@@ -163,12 +163,14 @@ class Project(models.Model):
 
     @api.depends('sale_line_employee_ids.sale_line_id', 'sale_line_id')
     def _compute_partner_id(self):
-        for project in self:
+        billable_projects = self.filtered('allow_billable')
+        for project in billable_projects:
             if project.partner_id:
                 continue
             if project.allow_billable and project.allow_timesheets and project.pricing_type != 'task_rate':
                 sol = project.sale_line_id or project.sale_line_employee_ids.sale_line_id[:1]
                 project.partner_id = sol.order_partner_id
+        super(Project, self - billable_projects)._compute_partner_id()
 
     @api.depends('partner_id')
     def _compute_sale_line_id(self):
diff --git a/addons/sale_timesheet/tests/test_project_billing.py b/addons/sale_timesheet/tests/test_project_billing.py
index b20547374ee..35665d3d99b 100644
--- a/addons/sale_timesheet/tests/test_project_billing.py
+++ b/addons/sale_timesheet/tests/test_project_billing.py
@@ -269,7 +269,7 @@ class TestProjectBilling(TestCommonSaleTimesheet):
 
         self.assertFalse(subtask.allow_billable, "Subtask in non billable project should be non billable too")
         self.assertFalse(subtask.project_id.allow_billable, "The subtask project is non billable even if the subtask is")
-        self.assertEqual(subtask.partner_id, subtask.parent_id.partner_id, "Subtask should have the same customer as the one from their mother")
+        self.assertFalse(subtask.partner_id, "Subtask in non billable project should not have a customer")
 
         # log timesheet on subtask
         timesheet2 = Timesheet.create({
@@ -367,7 +367,7 @@ class TestProjectBilling(TestCommonSaleTimesheet):
             'project_id': self.project_subtask.id,
         })
 
-        self.assertEqual(subtask.partner_id, subtask.parent_id.partner_id, "Subtask should have the same customer as the one from their mother")
+        self.assertFalse(subtask.partner_id, "Subtask should not have the customer if it's project is not billable")
 
         # log timesheet on subtask
         timesheet2 = Timesheet.create({
diff --git a/addons/sale_timesheet/views/project_task_views.xml b/addons/sale_timesheet/views/project_task_views.xml
index 07b2fa28a14..05ad66e377d 100644
--- a/addons/sale_timesheet/views/project_task_views.xml
+++ b/addons/sale_timesheet/views/project_task_views.xml
@@ -134,7 +134,7 @@
                     <field name="is_project_map_empty" invisible="1" groups="hr_timesheet.group_hr_timesheet_user"/>
                     <field name="has_multi_sol" invisible="1" groups="hr_timesheet.group_hr_timesheet_user"/>
                 </xpath>
-                 <xpath expr="//field[@name='partner_phone']" position="after">
+                 <xpath expr="//field[@name='partner_id']" position="after">
                     <field name="pricing_type" invisible="1" groups="hr_timesheet.group_hr_timesheet_user"/>
                 </xpath>
                 <xpath expr="//field[@name='timesheet_ids']" position="attributes">