feat: Type of Income Paid on Tax Withholding Category

Custom Select income_type: the row of the withholding tax certificate
(50 tawi) a payment under the category is reported on, set for every
shipped category.

Frappe syncs fixtures before customizations on install and migrate, so a
fixture value for a Custom Field that does not exist yet is dropped;
before_install / before_migrate create the category fields first.

default_thai_company/default_thai_company/custom/tax_withholding_category.json

@@ -0,0 +1,73 @@
+{
+ "custom_fields": [
+  {
+   "_assign": null,
+   "_comments": null,
+   "_liked_by": null,
+   "_user_tags": null,
+   "allow_in_quick_entry": 0,
+   "allow_on_submit": 0,
+   "bold": 0,
+   "collapsible": 0,
+   "collapsible_depends_on": null,
+   "columns": 0,
+   "creation": "2026-09-22 09:00:00.000000",
+   "default": null,
+   "depends_on": null,
+   "description": "Row of the withholding tax certificate (50 Tawi) the payment is reported on; Other prints the category name in row 6.",
+   "docstatus": 0,
+   "dt": "Tax Withholding Category",
+   "fetch_from": null,
+   "fetch_if_empty": 0,
+   "fieldname": "income_type",
+   "fieldtype": "Select",
+   "hidden": 0,
+   "hide_border": 0,
+   "hide_days": 0,
+   "hide_seconds": 0,
+   "idx": 2,
+   "ignore_user_permissions": 0,
+   "ignore_xss_filter": 0,
+   "in_global_search": 0,
+   "in_list_view": 0,
+   "in_preview": 0,
+   "in_standard_filter": 0,
+   "insert_after": "category_name",
+   "is_system_generated": 0,
+   "is_virtual": 0,
+   "label": "Type of Income Paid",
+   "length": 0,
+   "link_filters": null,
+   "mandatory_depends_on": null,
+   "modified": "2026-09-22 09:00:00.000000",
+   "modified_by": "Administrator",
+   "module": null,
+   "name": "Tax Withholding Category-income_type",
+   "no_copy": 0,
+   "non_negative": 0,
+   "options": "\nSalary and Wages - Sec. 40(1)\nFees and Commissions - Sec. 40(2)\nRoyalties - Sec. 40(3)\nInterest - Sec. 40(4)(a)\nDividends - Sec. 40(4)(b)\nSec. 3 Tera (Services, Rent, Contract Work etc.)\nOther",
+   "owner": "Administrator",
+   "permlevel": 0,
+   "placeholder": null,
+   "precision": null,
+   "print_hide": 0,
+   "print_hide_if_no_value": 0,
+   "print_width": null,
+   "read_only": 0,
+   "read_only_depends_on": null,
+   "report_hide": 0,
+   "reqd": 0,
+   "search_index": 0,
+   "show_dashboard": 0,
+   "sort_options": 0,
+   "translatable": 0,
+   "unique": 0,
+   "width": null
+  }
+ ],
+ "custom_perms": [],
+ "doctype": "Tax Withholding Category",
+ "links": [],
+ "property_setters": [],
+ "sync_on_migrate": 1
+}

default_thai_company/fixtures/tax_withholding_category.json

@@ -5,7 +5,8 @@
   "consider_party_ledger_amount": 0,
   "docstatus": 0,
   "doctype": "Tax Withholding Category",
-  "modified": "2026-09-11 09:00:00.000000",
+  "income_type": "Fees and Commissions - Sec. 40(2)",
+  "modified": "2026-09-22 12:00:00.000000",
   "name": "WHT 3% - Commission",
   "rates": [
    {
@@ -31,7 +32,8 @@
   "consider_party_ledger_amount": 0,
   "docstatus": 0,
   "doctype": "Tax Withholding Category",
-  "modified": "2026-09-11 09:00:00.000000",
+  "income_type": "Royalties - Sec. 40(3)",
+  "modified": "2026-09-22 12:00:00.000000",
   "name": "WHT 3% - Royalty",
   "rates": [
    {
@@ -57,7 +59,8 @@
   "consider_party_ledger_amount": 0,
   "docstatus": 0,
   "doctype": "Tax Withholding Category",
-  "modified": "2026-09-11 09:00:00.000000",
+  "income_type": "Interest - Sec. 40(4)(a)",
+  "modified": "2026-09-22 12:00:00.000000",
   "name": "WHT 1% - Interest (Company)",
   "rates": [
    {
@@ -83,7 +86,8 @@
   "consider_party_ledger_amount": 0,
   "docstatus": 0,
   "doctype": "Tax Withholding Category",
-  "modified": "2026-09-11 09:00:00.000000",
+  "income_type": "Interest - Sec. 40(4)(a)",
+  "modified": "2026-09-22 12:00:00.000000",
   "name": "WHT 15% - Interest (Individual)",
   "rates": [
    {
@@ -109,7 +113,8 @@
   "consider_party_ledger_amount": 0,
   "docstatus": 0,
   "doctype": "Tax Withholding Category",
-  "modified": "2026-09-11 09:00:00.000000",
+  "income_type": "Dividends - Sec. 40(4)(b)",
+  "modified": "2026-09-22 12:00:00.000000",
   "name": "WHT 10% - Dividend",
   "rates": [
    {
@@ -135,7 +140,8 @@
   "consider_party_ledger_amount": 0,
   "docstatus": 0,
   "doctype": "Tax Withholding Category",
-  "modified": "2026-09-11 09:00:00.000000",
+  "income_type": "Sec. 3 Tera (Services, Rent, Contract Work etc.)",
+  "modified": "2026-09-22 12:00:00.000000",
   "name": "WHT 5% - Rent",
   "rates": [
    {
@@ -161,7 +167,8 @@
   "consider_party_ledger_amount": 0,
   "docstatus": 0,
   "doctype": "Tax Withholding Category",
-  "modified": "2026-09-11 09:00:00.000000",
+  "income_type": "Sec. 3 Tera (Services, Rent, Contract Work etc.)",
+  "modified": "2026-09-22 12:00:00.000000",
   "name": "WHT 1% - Ship Rental",
   "rates": [
    {
@@ -187,7 +194,8 @@
   "consider_party_ledger_amount": 0,
   "docstatus": 0,
   "doctype": "Tax Withholding Category",
-  "modified": "2026-09-11 09:00:00.000000",
+  "income_type": "Sec. 3 Tera (Services, Rent, Contract Work etc.)",
+  "modified": "2026-09-22 12:00:00.000000",
   "name": "WHT 3% - Professional Fee",
   "rates": [
    {
@@ -213,7 +221,8 @@
   "consider_party_ledger_amount": 0,
   "docstatus": 0,
   "doctype": "Tax Withholding Category",
-  "modified": "2026-09-11 09:00:00.000000",
+  "income_type": "Sec. 3 Tera (Services, Rent, Contract Work etc.)",
+  "modified": "2026-09-22 12:00:00.000000",
   "name": "WHT 3% - Contract Work",
   "rates": [
    {
@@ -239,7 +248,8 @@
   "consider_party_ledger_amount": 0,
   "docstatus": 0,
   "doctype": "Tax Withholding Category",
-  "modified": "2026-09-11 09:00:00.000000",
+  "income_type": "Sec. 3 Tera (Services, Rent, Contract Work etc.)",
+  "modified": "2026-09-22 12:00:00.000000",
   "name": "WHT 3% - Service",
   "rates": [
    {
@@ -265,7 +275,8 @@
   "consider_party_ledger_amount": 0,
   "docstatus": 0,
   "doctype": "Tax Withholding Category",
-  "modified": "2026-09-11 09:00:00.000000",
+  "income_type": "Sec. 3 Tera (Services, Rent, Contract Work etc.)",
+  "modified": "2026-09-22 12:00:00.000000",
   "name": "WHT 3% - Sales Promotion",
   "rates": [
    {
@@ -291,7 +302,8 @@
   "consider_party_ledger_amount": 0,
   "docstatus": 0,
   "doctype": "Tax Withholding Category",
-  "modified": "2026-09-11 09:00:00.000000",
+  "income_type": "Sec. 3 Tera (Services, Rent, Contract Work etc.)",
+  "modified": "2026-09-22 12:00:00.000000",
   "name": "WHT 2% - Advertising",
   "rates": [
    {
@@ -317,7 +329,8 @@
   "consider_party_ledger_amount": 0,
   "docstatus": 0,
   "doctype": "Tax Withholding Category",
-  "modified": "2026-09-11 09:00:00.000000",
+  "income_type": "Sec. 3 Tera (Services, Rent, Contract Work etc.)",
+  "modified": "2026-09-22 12:00:00.000000",
   "name": "WHT 1% - Transportation",
   "rates": [
    {
@@ -343,7 +356,8 @@
   "consider_party_ledger_amount": 0,
   "docstatus": 0,
   "doctype": "Tax Withholding Category",
-  "modified": "2026-09-11 09:00:00.000000",
+  "income_type": "Sec. 3 Tera (Services, Rent, Contract Work etc.)",
+  "modified": "2026-09-22 12:00:00.000000",
   "name": "WHT 1% - Non-Life Insurance",
   "rates": [
    {
@@ -369,7 +383,8 @@
   "consider_party_ledger_amount": 0,
   "docstatus": 0,
   "doctype": "Tax Withholding Category",
-  "modified": "2026-09-11 09:00:00.000000",
+  "income_type": "Sec. 3 Tera (Services, Rent, Contract Work etc.)",
+  "modified": "2026-09-22 12:00:00.000000",
   "name": "WHT 5% - Prize",
   "rates": [
    {
@@ -395,7 +410,8 @@
   "consider_party_ledger_amount": 0,
   "docstatus": 0,
   "doctype": "Tax Withholding Category",
-  "modified": "2026-09-11 09:00:00.000000",
+  "income_type": "Sec. 3 Tera (Services, Rent, Contract Work etc.)",
+  "modified": "2026-09-22 12:00:00.000000",
   "name": "WHT 5% - Public Entertainer",
   "rates": [
    {
@@ -421,7 +437,8 @@
   "consider_party_ledger_amount": 0,
   "docstatus": 0,
   "doctype": "Tax Withholding Category",
-  "modified": "2026-09-11 09:00:00.000000",
+  "income_type": "Sec. 3 Tera (Services, Rent, Contract Work etc.)",
+  "modified": "2026-09-22 12:00:00.000000",
   "name": "WHT 0.75% - Agricultural Produce",
   "rates": [
    {
@@ -447,7 +464,8 @@
   "consider_party_ledger_amount": 0,
   "docstatus": 0,
   "doctype": "Tax Withholding Category",
-  "modified": "2026-09-11 09:00:00.000000",
+  "income_type": "Sec. 3 Tera (Services, Rent, Contract Work etc.)",
+  "modified": "2026-09-22 12:00:00.000000",
   "name": "WHT 1% - Aquatic Animals",
   "rates": [
    {
@@ -473,7 +491,8 @@
   "consider_party_ledger_amount": 0,
   "docstatus": 0,
   "doctype": "Tax Withholding Category",
-  "modified": "2026-09-11 09:00:00.000000",
+  "income_type": "Other",
+  "modified": "2026-09-22 12:00:00.000000",
   "name": "WHT 1% - Immovable Property (Company)",
   "rates": [
    {
@@ -499,7 +518,8 @@
   "consider_party_ledger_amount": 0,
   "docstatus": 0,
   "doctype": "Tax Withholding Category",
-  "modified": "2026-09-11 09:00:00.000000",
+  "income_type": "Other",
+  "modified": "2026-09-22 12:00:00.000000",
   "name": "WHT 15% - Non-Resident Individual",
   "rates": [
    {
@@ -525,7 +545,8 @@
   "consider_party_ledger_amount": 0,
   "docstatus": 0,
   "doctype": "Tax Withholding Category",
-  "modified": "2026-09-11 09:00:00.000000",
+  "income_type": "Other",
+  "modified": "2026-09-22 12:00:00.000000",
   "name": "WHT 15% - Foreign Company",
   "rates": [
    {
@@ -551,7 +572,8 @@
   "consider_party_ledger_amount": 0,
   "docstatus": 0,
   "doctype": "Tax Withholding Category",
-  "modified": "2026-09-11 09:00:00.000000",
+  "income_type": "Other",
+  "modified": "2026-09-22 12:00:00.000000",
   "name": "WHT 10% - Foreign Company Dividend",
   "rates": [
    {

default_thai_company/hooks.py

@@ -138,7 +138,10 @@ fixtures = [
 # Installation
 # ------------
 
-# before_install = "default_thai_company.install.before_install"
+# Fixtures are synced before Custom Fields on install and migrate; the Tax Withholding
+# Category fixtures carry values for the app's Custom Fields, so create those first.
+before_install = "default_thai_company.tax_withholding.sync_category_customizations"
+before_migrate = "default_thai_company.tax_withholding.sync_category_customizations"
 # Fixtures are synced before this runs; VAT schemes and Shipping Rules for companies
 # that already exist.
 after_install = [

default_thai_company/tax_withholding.py

@@ -1,3 +1,6 @@
+import json
+import os
+
 import erpnext
 import frappe
 from erpnext.accounts.doctype.payment_entry.payment_entry import PaymentEntry
@@ -8,6 +11,7 @@ from erpnext.accounts.doctype.tax_withholding_category.tax_withholding_category
 	normal_round,
 )
 from frappe import _
+from frappe.modules.utils import sync_customizations_for_doctype
 from frappe.utils import cint, flt
 
 from default_thai_company.utils import money_in_words
@@ -122,6 +126,17 @@ def prepare_fixture_accounts(doc, method=None):
 			link_company(doc, company, ensure_company_accounts(company))
 
 
+def sync_category_customizations():
+	"""before_install / before_migrate: create the Tax Withholding Category Custom
+	Fields (custom/tax_withholding_category.json) ahead of the fixture import.
+	Frappe syncs fixtures before customizations, and a fixture value for a field
+	that does not exist yet is dropped."""
+	folder = frappe.get_app_path("default_thai_company", "default_thai_company", "custom")
+	filename = "tax_withholding_category.json"
+	with open(os.path.join(folder, filename)) as f:
+		sync_customizations_for_doctype(json.load(f), folder, filename)
+
+
 def company_ready(doc):
 	"""A Thai company whose chart of accounts exists."""
 	return doc.country == "Thailand" and frappe.db.exists("Account", {"company": doc.name})

default_thai_company/tests/test_tax_withholding.py

@@ -27,12 +27,13 @@ class TestTaxWithholding(FrappeTestCase):
 	@classmethod
 	def setUpClass(cls):
 		super().setUpClass()
-		# Fixture categories must exist before the company is created so the
-		# Company hook has something to link; force=True re-imports.
-		import_file_by_path(FIXTURE, force=True, data_import=True)
-		for fname in ("sales_invoice.json", "payment_entry.json"):
+		# Custom Fields first: the category fixtures carry income_type. Fixture
+		# categories must exist before the company is created so the Company hook
+		# has something to link; force=True re-imports.
+		for fname in ("tax_withholding_category.json", "sales_invoice.json", "payment_entry.json"):
 			with open(f"{CUSTOM_DIR}/{fname}") as f:
 				sync_customizations_for_doctype(json.load(f), CUSTOM_DIR, fname)
+		import_file_by_path(FIXTURE, force=True, data_import=True)
 
 		frappe.get_doc(
 			{

default_thai_company/translations/th.csv

@@ -60,3 +60,10 @@ Withholding Tax Payable,ภาษีหัก ณ ที่จ่ายค้า
 Withholding Tax Receivable,ภาษีถูกหัก ณ ที่จ่าย
 Output VAT,ภาษีขาย
 Input VAT,ภาษีซื้อ
+Type of Income Paid,ประเภทเงินได้พึงประเมินที่จ่าย
+Salary and Wages - Sec. 40(1),เงินเดือน ค่าจ้าง ฯลฯ ตามมาตรา 40(1)
+Fees and Commissions - Sec. 40(2),ค่าธรรมเนียม ค่านายหน้า ฯลฯ ตามมาตรา 40(2)
+Royalties - Sec. 40(3),ค่าแห่งลิขสิทธิ์ ฯลฯ ตามมาตรา 40(3)
+Interest - Sec. 40(4)(a),ดอกเบี้ย ฯลฯ ตามมาตรา 40(4)(ก)
+Dividends - Sec. 40(4)(b),เงินปันผล เงินส่วนแบ่งกำไร ฯลฯ ตามมาตรา 40(4)(ข)
+"Sec. 3 Tera (Services, Rent, Contract Work etc.)",ตามคำสั่งกรมสรรพากรที่ออกตามมาตรา 3 เตรส (ค่าบริการ ค่าเช่า ค่าจ้างทำของ ฯลฯ)