From a464a6e4a1fcc4d062e5c7cc47fe92a9f45d9d5f Mon Sep 17 00:00:00 2001
From: Mihir Kandoi <kandoimihir@gmail.com>
Date: Fri, 7 Aug 2026 13:04:45 +0530
Subject: [PATCH 1/2] fix: UOM whole number check truncated instead of rounding

cint truncates, so a stock_qty of 1999.9998 (dust from qty times
conversion factor) compared as abs(1999 - 2000.0) > epsilon and was
rejected as fractional even though it rounds to a whole number at
field precision, with the error confusingly printing the rounded
value: 'Quantity (2000.0) cannot be a fraction'. Round to field
precision first, then require the result to be a whole number.
Dust above an integer already passed; this fixes the asymmetry for
dust below.
---
 erpnext/utilities/transaction_base.py | 6 +++---
 1 file changed, 3 insertions(+), 3 deletions(-)

diff --git a/erpnext/utilities/transaction_base.py b/erpnext/utilities/transaction_base.py
index e49660f33c0..07e9c40ebd7 100644
--- a/erpnext/utilities/transaction_base.py
+++ b/erpnext/utilities/transaction_base.py
@@ -618,13 +618,13 @@ def validate_uom_is_integer(doc, uom_field, qty_fields, child_dt=None):
 			for f in qty_fields:
 				qty = d.get(f)
 				if qty:
-					precision = d.precision(f)
-					if abs(cint(qty) - flt(qty, precision)) > 0.0000001:
+					qty = flt(qty, d.precision(f))
+					if qty != cint(qty):
 						frappe.throw(
 							_(
 								"Row {1}: Quantity ({0}) cannot be a fraction. To allow this, disable '{2}' in UOM {3}."
 							).format(
-								flt(qty, precision),
+								qty,
 								d.idx,
 								frappe.bold(_("Must be Whole Number")),
 								frappe.bold(d.get(uom_field)),

From e6a6458ebeab882a47459965d192aac254b00892 Mon Sep 17 00:00:00 2001
From: Mihir Kandoi <kandoimihir@gmail.com>
Date: Fri, 7 Aug 2026 13:06:57 +0530
Subject: [PATCH 2/2] test: UOM whole number check tolerates conversion dust

---
 .../purchase_order/test_purchase_order.py     | 19 +++++++++++++++++++
 1 file changed, 19 insertions(+)

diff --git a/erpnext/buying/doctype/purchase_order/test_purchase_order.py b/erpnext/buying/doctype/purchase_order/test_purchase_order.py
index 05c6542939d..a9da89a8306 100644
--- a/erpnext/buying/doctype/purchase_order/test_purchase_order.py
+++ b/erpnext/buying/doctype/purchase_order/test_purchase_order.py
@@ -724,6 +724,25 @@ class TestPurchaseOrder(ERPNextTestSuite):
 		below_minimum.items[0].conversion_factor = 0.6
 		self.assertRaises(frappe.ValidationError, below_minimum.insert)
 
+	def test_uom_integer_check_tolerates_conversion_dust(self):
+		from erpnext.utilities.transaction_base import UOMMustBeIntegerError
+
+		item_doc = make_item(properties={"stock_uom": "Nos"})
+		item_doc.append("uoms", {"uom": "Kg", "conversion_factor": 0.6})
+		item_doc.save()
+		item = item_doc.name
+
+		precision = frappe.get_precision("Purchase Order Item", "stock_qty")
+		po = create_purchase_order(item_code=item, qty=flt(2000 / 0.6, precision), do_not_save=1)
+		po.items[0].uom = "Kg"
+		po.items[0].conversion_factor = 0.6
+		po.insert()
+
+		fractional = create_purchase_order(item_code=item, qty=3333.9, do_not_save=1)
+		fractional.items[0].uom = "Kg"
+		fractional.items[0].conversion_factor = 0.6
+		self.assertRaises(UOMMustBeIntegerError, fractional.insert)
+
 	def test_ordered_qty_for_closing_po(self):
 		bin = frappe.get_all(
 			"Bin",