diff --git a/CHANGELOG b/CHANGELOG
index dbcdbddfe6..38b60f7009 100644
--- a/CHANGELOG
+++ b/CHANGELOG
@@ -1,3 +1,4 @@
+* Allow creating manual commission
 * Include commission to stock margin report
 
 Version 6.4.0 - 2022-05-02
diff --git a/commission.py b/commission.py
index 84f0fecd8f..521b2387a2 100644
--- a/commission.py
+++ b/commission.py
@@ -333,8 +333,8 @@ class Commission(ModelSQL, ModelView):
     _readonly_states = {
         'readonly': Bool(Eval('invoice_line')),
         }
-    origin = fields.Reference('Origin', selection='get_origin', select=True,
-        readonly=True,
+    origin = fields.Reference(
+        "Origin", selection='get_origin', select=True, states=_readonly_states,
         help="The source of the commission.")
     date = fields.Date('Date', select=True, states=_readonly_states,
         help="When the commission is due.")
@@ -392,6 +392,20 @@ class Commission(ModelSQL, ModelView):
         models = cls._get_origin()
         return [(None, '')] + [(m, get_name(m)) for m in models]
 
+    @fields.depends('agent', 'origin', 'base_amount')
+    def on_change_with_base_amount(self):
+        pool = Pool()
+        InvoiceLine = pool.get('account.invoice.line')
+        Currency = pool.get('currency.currency')
+        if (self.agent
+                and isinstance(self.origin, InvoiceLine)
+                and self.origin.id is not None
+                and self.origin.id >= 0
+                and self.base_amount is None):
+            return Currency.compute(
+                self.origin.invoice.currency, self.origin.amount,
+                self.agent.currency, round=False)
+
     @fields.depends('agent')
     def on_change_with_currency(self, name=None):
         if self.agent:
diff --git a/invoice.py b/invoice.py
index 9681c20eac..9b8efa13c0 100644
--- a/invoice.py
+++ b/invoice.py
@@ -137,6 +137,7 @@ class InvoiceLine(metaclass=PoolMeta):
             'invisible': If(Bool(Eval('_parent_invoice')),
                 Eval('_parent_invoice', {}).get('type') == 'in',
                 Eval('invoice_type') == 'in'),
+            'readonly': Eval('invoice_state') != 'draft',
             },
         help="The principal who pays a commission for the invoice line.")
     commissions = fields.One2Many('commission', 'origin', 'Commissions',
diff --git a/view/commission_form.xml b/view/commission_form.xml
index a4c70c34de..4bac0da94b 100644
--- a/view/commission_form.xml
+++ b/view/commission_form.xml
@@ -11,14 +11,15 @@ this repository contains the full copyright notices and license terms. -->
     <label name="product"/>
     <field name="product"/>
 
+    <label name="origin"/>
+    <field name="origin"/>
+    <newline/>
+
     <label name="base_amount"/>
     <field name="base_amount"/>
     <label name="amount"/>
     <field name="amount"/>
 
-    <label name="origin"/>
-    <field name="origin"/>
-    <newline/>
     <label name="invoice_line"/>
     <field name="invoice_line"/>
     <label name="invoice_state"/>