diff --git a/addons/account/models/account_move.py b/addons/account/models/account_move.py
index 96a0578844b..0841eed48fe 100644
--- a/addons/account/models/account_move.py
+++ b/addons/account/models/account_move.py
@@ -2651,8 +2651,27 @@ class AccountMove(models.Model):
                     self.journal_id.company_id.account_purchase_tax_id
                 )
             taxes = self.fiscal_position_id.map_tax(taxes)
-        price_untaxed = taxes.with_context(force_price_include=True).compute_all(
-            self.quick_edit_total_amount - self.tax_totals['amount_total'])['total_excluded']
+
+        # When a payment term has an early payment discount with the epd computation set to 'mixed', recomputing
+        # the untaxed amount should take in consideration the discount percentage otherwise we'd get a wrong value.
+        # We check that we have only one percentage tax as computing from multiple taxes with different types can get complicated.
+        # In one example: let's say: base = 100, discount = 2%, tax = 21%
+        # the total will be calculated as: total = base + (base * (1 - discount)) * tax
+        # If we manipulate the equation to get the base from the total, we'll have base = total / ((1 - discount) * tax + 1)
+        term = self.invoice_payment_term_id
+        discount_percentage = term.discount_percentage if term.early_discount else 0
+        remaining_amount = self.quick_edit_total_amount - self.tax_totals['amount_total']
+
+        if (
+                discount_percentage
+                and term.early_pay_discount_computation == 'mixed'
+                and len(taxes) == 1
+                and taxes.amount_type == 'percent'
+        ):
+            price_untaxed = self.currency_id.round(
+                remaining_amount / (((1.0 - discount_percentage / 100.0) * (taxes.amount / 100.0)) + 1.0))
+        else:
+            price_untaxed = taxes.with_context(force_price_include=True).compute_all(remaining_amount)['total_excluded']
         return {'account_id': account_id, 'tax_ids': taxes.ids, 'price_unit': price_untaxed}
 
     @api.onchange('quick_edit_mode', 'journal_id', 'company_id')
diff --git a/addons/account/tests/test_account_move_out_invoice.py b/addons/account/tests/test_account_move_out_invoice.py
index 88afc0e3de2..dec0096eb36 100644
--- a/addons/account/tests/test_account_move_out_invoice.py
+++ b/addons/account/tests/test_account_move_out_invoice.py
@@ -3344,6 +3344,55 @@ class TestAccountMoveOutInvoiceOnchanges(AccountTestInvoicingCommon):
         self.assertEqual(invoice.amount_tax, 17.36)
         self.assertEqual(len(invoice.invoice_line_ids), 2)
 
+    def test_quick_edit_total_amount_with_mixed_epd(self):
+        move_form = Form(self.env['account.move'].with_context(default_move_type='out_invoice'))
+        move_form.invoice_date = fields.Date.from_string('2022-01-01')
+
+        # Quick edit total amount activated
+        self.env.company.quick_edit_mode = "out_and_in_invoices"
+        # 21% sale tax
+        self.env.company.account_sale_tax_id = self.env['account.tax'].create({
+            'name': '21%',
+            'amount': 21,
+            'type_tax_use': 'sale',
+        })
+        # Create a payment term with early payment discount of 2%  and computation set to mixed (Always (upon invoice))
+        epd_payment_term = self.env['account.payment.term'].create({
+            'name': "2/7 Term",
+            'discount_days': 7,
+            'discount_percentage': 2,
+            'early_discount': True,
+            'early_pay_discount_computation': 'mixed',
+        })
+        # Set the payment term to the one we just created
+        move_form.invoice_payment_term_id = epd_payment_term
+
+        invoice = move_form.save()
+
+        # Invoice of one item of price 100, discount 2% and tax 21%:
+        # 21% tax = 100 * (1 - 0.2) * 0.21 = 20.58
+        # total_amount = 100 + 20.58 = 120.58
+
+        # Make sure the quick edit added one line with the correct values
+        with Form(invoice) as move_form:
+            move_form.quick_edit_total_amount = 120.58
+        self.assertRecordValues(invoice, [{'amount_total': 120.58, 'amount_untaxed': 100, 'amount_tax': 20.58}])
+        self.assertEqual(len(invoice.invoice_line_ids), 1)
+
+        # Modify one invoice line
+        with Form(invoice) as move_form:
+            with move_form.invoice_line_ids.edit(0) as line_form:
+                line_form.price_unit = 70
+        self.assertRecordValues(invoice, [{'amount_total': 84.41, 'amount_untaxed': 70, 'amount_tax': 14.41}])
+        self.assertEqual(len(invoice.invoice_line_ids), 1)
+
+        # Suggest the new amount such that the total is equal to the quick amount
+        with Form(invoice) as move_form:
+            with move_form.invoice_line_ids.new() as line_form:
+                self.assertEqual(line_form.price_unit, 30)
+        self.assertRecordValues(invoice, [{'amount_total': 120.58, 'amount_untaxed': 100, 'amount_tax': 20.58}])
+        self.assertEqual(len(invoice.invoice_line_ids), 2)
+
     def test_out_invoice_depreciated_account(self):
         move = self.env['account.move'].create({
             'move_type': 'out_invoice',