diff --git a/erpnext/controllers/taxes_and_totals.py b/erpnext/controllers/taxes_and_totals.py
index b44f597..41ba61b 100644
--- a/erpnext/controllers/taxes_and_totals.py
+++ b/erpnext/controllers/taxes_and_totals.py
@@ -600,16 +600,19 @@
 			for item_code, tax_data in item_tax_map.items():
 				itemised_tax.setdefault(item_code, frappe._dict())
 
+				tax_rate = 0.0
+				tax_amount = 0.0
+
 				if isinstance(tax_data, list):
-					itemised_tax[item_code][tax.description] = frappe._dict(dict(
-						tax_rate=flt(tax_data[0]),
-						tax_amount=flt(tax_data[1])
-					))
+					tax_rate = flt(tax_data[0])
+					tax_amount = flt(tax_data[1])
 				else:
-					itemised_tax[item_code][tax.description] = frappe._dict(dict(
-						tax_rate=flt(tax_data),
-						tax_amount=0.0
-					))
+					tax_rate = flt(tax_data)
+
+				itemised_tax[item_code][tax.description] = frappe._dict(dict(
+					tax_rate = tax_rate,
+					tax_amount = tax_amount
+				))
 
 	return itemised_tax
 
diff --git a/erpnext/public/js/controllers/taxes_and_totals.js b/erpnext/public/js/controllers/taxes_and_totals.js
index f00b84f..865a5ff 100644
--- a/erpnext/public/js/controllers/taxes_and_totals.js
+++ b/erpnext/public/js/controllers/taxes_and_totals.js
@@ -338,12 +338,18 @@
 
 	set_item_wise_tax: function(item, tax, tax_rate, current_tax_amount) {
 		// store tax breakup for each item
-		var key = item.item_code || item.item_name;
-		var item_wise_tax_amount = current_tax_amount * this.frm.doc.conversion_rate;
-		if (tax.item_wise_tax_detail && tax.item_wise_tax_detail[key])
-			item_wise_tax_amount += tax.item_wise_tax_detail[key][1];
+		let tax_detail = tax.item_wise_tax_detail;
 
-		tax.item_wise_tax_detail[key] = [tax_rate, flt(item_wise_tax_amount, precision("base_tax_amount", tax))];
+		let key = item.item_code;
+		if(item.item_name && !Object.keys(tax_detail).includes(item.item_name)) {
+			key = item.item_name;
+		}
+
+		let item_wise_tax_amount = current_tax_amount * this.frm.doc.conversion_rate;
+		if (tax_detail && tax_detail[key])
+			item_wise_tax_amount += tax_detail[key][1];
+
+		tax_detail[key] = [tax_rate, flt(item_wise_tax_amount, precision("base_tax_amount", tax))];
 	},
 
 	round_off_totals: function(tax) {