From a908bc7e92062c26dc8d41ff303885b6f84a2975 Mon Sep 17 00:00:00 2001
From: diptanilsaha <diptanil@frappe.io>
Date: Mon, 23 Mar 2026 14:23:42 +0530
Subject: [PATCH] fix(trends): added validation for `period_based_on` filter
 (#53690)

---
 erpnext/controllers/trends.py | 8 ++++++++
 1 file changed, 8 insertions(+)

diff --git a/erpnext/controllers/trends.py b/erpnext/controllers/trends.py
index 752ec87d501..bde00074ecb 100644
--- a/erpnext/controllers/trends.py
+++ b/erpnext/controllers/trends.py
@@ -55,6 +55,14 @@ def validate_filters(filters):
 	if filters.get("based_on") == filters.get("group_by"):
 		frappe.throw(_("'Based On' and 'Group By' can not be same"))
 
+	if filters.get("period_based_on") and filters.period_based_on not in ["bill_date", "posting_date"]:
+		frappe.throw(
+			msg=_("{0} can be either {1} or {2}.").format(
+				frappe.bold("Period based On"), frappe.bold("Posting Date"), frappe.bold("Billing Date")
+			),
+			title=_("Invalid Filter"),
+		)
+
 
 def get_data(filters, conditions):
 	data = []