diff --git a/erpnext/buying/doctype/supplier/supplier_import_provider.py b/erpnext/buying/doctype/supplier/supplier_import_provider.py
index 67a152e74b3..fd03c4814ac 100644
--- a/erpnext/buying/doctype/supplier/supplier_import_provider.py
+++ b/erpnext/buying/doctype/supplier/supplier_import_provider.py
@@ -176,7 +176,10 @@ class SupplierImportProvider(ImportProvider):
 			if flagged or primary is None:
 				primary = address
 		if primary:
-			frappe.db.set_value("Address", primary.name, "is_primary_address", 1)
+			# Save (not db.set_value) so Address.validate_preferred_address() clears any
+			# existing primary address on the party — a raw write would leave two flagged.
+			primary.is_primary_address = 1
+			primary.save()
 			supplier.db_set("supplier_primary_address", primary.name)
 			supplier.db_set("primary_address", get_address_display(primary.name))
 
diff --git a/erpnext/selling/doctype/customer/customer_import_provider.py b/erpnext/selling/doctype/customer/customer_import_provider.py
index 24d5256993f..cc5c7bd230f 100644
--- a/erpnext/selling/doctype/customer/customer_import_provider.py
+++ b/erpnext/selling/doctype/customer/customer_import_provider.py
@@ -184,7 +184,10 @@ class CustomerImportProvider(ImportProvider):
 			if flagged or primary is None:
 				primary = address
 		if primary:
-			frappe.db.set_value("Address", primary.name, "is_primary_address", 1)
+			# Save (not db.set_value) so Address.validate_preferred_address() clears any
+			# existing primary address on the party — a raw write would leave two flagged.
+			primary.is_primary_address = 1
+			primary.save()
 			customer.db_set("customer_primary_address", primary.name)
 			customer.db_set("primary_address", get_address_display(primary.name))