diff --git a/erpnext/projects/doctype/timesheet_detail/timesheet_detail.py b/erpnext/projects/doctype/timesheet_detail/timesheet_detail.py
index 3dbb8614fa4..1ce2e7977d5 100644
--- a/erpnext/projects/doctype/timesheet_detail/timesheet_detail.py
+++ b/erpnext/projects/doctype/timesheet_detail/timesheet_detail.py
@@ -90,7 +90,7 @@ class TimesheetDetail(Document):
 		)
 
 		self.billing_amount = self.billing_rate * (self.billing_hours or 0)
-		self.costing_amount = self.costing_rate * (self.billing_hours or self.hours or 0)
+		self.costing_amount = self.costing_rate * (self.hours or 0)
 
 	def validate_dates(self):
 		"""Validate that to_time is not before from_time."""