diff --git a/addons/sale_timesheet/models/project.py b/addons/sale_timesheet/models/project.py
index 7d29162024b..f2dbb291619 100644
--- a/addons/sale_timesheet/models/project.py
+++ b/addons/sale_timesheet/models/project.py
@@ -121,11 +121,12 @@ class Project(models.Model):
 class ProjectTask(models.Model):
     _inherit = "project.task"
 
-    sale_line_id = fields.Many2one('sale.order.line', 'Sales Order Item', domain="[('is_service', '=', True), ('order_partner_id', 'child_of', commercial_partner_id), ('is_expense', '=', False), ('state', 'in', ['sale', 'done'])]",
+    sale_line_id = fields.Many2one('sale.order.line', 'Sales Order Item', domain="[('is_service', '=', True), ('order_partner_id', 'child_of', commercial_partner_id), ('is_expense', '=', False), ('state', 'in', ['sale', 'done']), ('order_id', '=?', project_sale_order_id)]",
         compute='_compute_sale_line', store=True, readonly=False,
         help="Sales order item to which the task is linked. If an employee timesheets on a this task, "
         "and if this employee is not in the 'Employee/Sales Order Item Mapping' of the project, the "
         "timesheet entry will be linked to this sales order item.", copy=False)
+    project_sale_order_id = fields.Many2one('sale.order', string="project's sale order", related='project_id.sale_order_id')
     sale_order_id = fields.Many2one('sale.order', 'Sales Order', compute='_compute_sale_order_id', store=True, readonly=False, help="Sales order to which the task is linked.")
     billable_type = fields.Selection([
         ('task_rate', 'At Task Rate'),
@@ -161,7 +162,7 @@ class ProjectTask(models.Model):
 
     @api.onchange('project_id')
     def _onchange_project(self):
-        result = super(ProjectTask, self)._onchange_project()
+        super(ProjectTask, self)._onchange_project()
         if self.project_id:
             if self.project_id.billable_type == 'employee_rate':
                 if not self.partner_id:
@@ -172,12 +173,6 @@ class ProjectTask(models.Model):
                 if not self.partner_id:
                     self.partner_id = self.sale_line_id.order_partner_id
         # set domain on SO: on non billable project, all SOL of customer, otherwise the one from the SO
-        result = result or {}
-        domain = [('is_service', '=', True), ('is_expense', '=', False), ('order_partner_id', 'child_of', self.partner_id.commercial_partner_id.id), ('state', 'in', ['sale', 'done'])]
-        if self.project_id.sale_order_id:
-            domain += [('order_id', '=', self.project_id.sale_order_id.id)]
-        result.setdefault('domain', {})['sale_line_id'] = domain
-        return result
 
     @api.depends('project_id.sale_line_id.order_partner_id')
     def _compute_partner_id(self):
diff --git a/addons/sale_timesheet/views/project_task_views.xml b/addons/sale_timesheet/views/project_task_views.xml
index e1ba57d9baf..445095f118b 100644
--- a/addons/sale_timesheet/views/project_task_views.xml
+++ b/addons/sale_timesheet/views/project_task_views.xml
@@ -73,6 +73,7 @@
                     <field name="billable_type" invisible="1"/>
                     <field name="sale_order_id" attrs="{'invisible': [('project_id', '!=', False)]}" groups="sales_team.group_sale_salesman"/>
                     <field name="commercial_partner_id" invisible="1" />
+                    <field name="project_sale_order_id" invisible="1"/>
                 </xpath>
             </field>
         </record>
diff --git a/addons/sale_timesheet/wizard/project_create_invoice.py b/addons/sale_timesheet/wizard/project_create_invoice.py
index c159d788df8..54b964a54f0 100644
--- a/addons/sale_timesheet/wizard/project_create_invoice.py
+++ b/addons/sale_timesheet/wizard/project_create_invoice.py
@@ -23,16 +23,20 @@ class ProjectCreateInvoice(models.TransientModel):
         return result
 
     project_id = fields.Many2one('project.project', "Project", help="Project to make billable", required=True)
-    sale_order_id = fields.Many2one('sale.order', string="Choose the Sales Order to invoice", required=True)
+    _candidate_orders = fields.Many2many('sale.order', compute='_compute_candidate_orders')
+    sale_order_id = fields.Many2one(
+        'sale.order', string="Choose the Sales Order to invoice", required=True,
+        domain="[('id', 'in', _candidate_orders)]"
+    )
     amount_to_invoice = fields.Monetary("Amount to invoice", compute='_compute_amount_to_invoice', currency_field='currency_id', help="Total amount to invoice on the sales order, including all items (services, storables, expenses, ...)")
     currency_id = fields.Many2one(related='sale_order_id.currency_id', readonly=True)
 
-    @api.onchange('project_id')
-    def _onchange_project_id(self):
-        sale_orders = self.project_id.tasks.mapped('sale_line_id.order_id').filtered(lambda so: so.invoice_status == 'to invoice')
-        return {
-            'domain': {'sale_order_id': [('id', 'in', sale_orders.ids)]},
-        }
+    @api.depends('project_id.tasks.sale_line_id.order_id.invoice_status')
+    def _compute_candidate_orders(self):
+        for p in self:
+            p._candidate_orders = p.project_id\
+                .mapped('tasks.sale_line_id.order_id')\
+                .filtered(lambda so: so.invoice_status == 'to invoice')
 
     @api.depends('sale_order_id')
     def _compute_amount_to_invoice(self):
diff --git a/addons/sale_timesheet/wizard/project_create_invoice_views.xml b/addons/sale_timesheet/wizard/project_create_invoice_views.xml
index 9d6f2f1b96f..191cab2c0c4 100644
--- a/addons/sale_timesheet/wizard/project_create_invoice_views.xml
+++ b/addons/sale_timesheet/wizard/project_create_invoice_views.xml
@@ -8,6 +8,7 @@
             <form string="Create Sales Order from Project">
                 <group>
                     <field name="project_id" readonly="1"/>
+                    <field name="_candidate_orders" invisible="1"/>
                     <field name="sale_order_id" options="{'no_create_edit': True}" context="{'sale_show_partner_name': True}"/>
                     <field name="amount_to_invoice"/>
                 </group>