https://docs.whmcs.com/9-1/tags/vat/Recent content in vat onHugo -- gohugo.iohttps://docs.whmcs.com/9-1/payments/tax-configuration/Mon, 01 Jan 0001 00:00:00 +0000https://docs.whmcs.com/9-1/payments/tax-configuration/Details General Settings fields like Tax/VAT ID Number and Inclusive/Exclusive Tax, VAT Settings fields including VAT Mode, VAT Number Validation, and UK VAT Validation Mode, steps to add or update tax rules, and Advanced Settings for Taxed Items and Calculation Mode.https://docs.whmcs.com/9-1/clients/the-client-area/custom-fields/Mon, 01 Jan 0001 00:00:00 +0000https://docs.whmcs.com/9-1/clients/the-client-area/custom-fields/Covers creating Client, Product, and Support Department custom fields with field types (Text Box, Password, Drop Down, Checkbox), Admin Only, Required Field, Show on Order Form, and Show on Invoice options, display names, regular expression validation, searching by custom field values, and merge field syntax for displaying values in emails and pages.https://docs.whmcs.com/9-1/billing-and-invoicing/invoicing-tutorials/customize-the-invoice-number-format/Mon, 01 Jan 0001 00:00:00 +0000https://docs.whmcs.com/9-1/billing-and-invoicing/invoicing-tutorials/customize-the-invoice-number-format/Steps through enabling Tax Support and Custom Invoice Numbering in Tax Configuration, setting the Custom Invoice Numbering Format using the NUMBER, YEAR, MONTH, and DAY tags, and specifying the Next Invoice Number, with example format outputs.https://docs.whmcs.com/9-1/billing-and-invoicing/invoicing-tutorials/enable-proforma-invoicing/Mon, 01 Jan 0001 00:00:00 +0000https://docs.whmcs.com/9-1/billing-and-invoicing/invoicing-tutorials/enable-proforma-invoicing/Steps through enabling Tax Support and Proforma Invoicing/Sequential Paid Invoice Numbering in Tax Configuration’s VAT Settings, setting the Sequential Invoice Number Format, Next Paid Invoice Number, and Auto Reset Numbering, then enabling Enable Proforma Invoicing in the General Settings Invoices tab.https://docs.whmcs.com/9-1/system/general-settings/general-settings-invoices/Mon, 01 Jan 0001 00:00:00 +0000https://docs.whmcs.com/9-1/system/general-settings/general-settings-invoices/Documents Continuous Invoice Generation, Metric Usage Invoicing, PDF Invoices/Paper Size/Font Family, Store Client Data Snapshot, Mass Payment, Clients Choose Gateway (including its effect on API-driven invoice gateway changes), Group Similar Line Items, Cancellation Request Handling, Automatic Subscription Management, Proforma Invoicing, Sequential Paid Invoice Numbering, invoice/credit/debit note number incrementation, late fee type and amount, and accepted credit card types. Also documents the Invoice Immutability compliance selector, its three states (full compliance, immutability disabled with credit and debit notes, and immutability and credit and debit note generation disabled), and the confirmation window that gates the disabled states.https://docs.whmcs.com/9-1/payments/tax-tutorials/update-tax-rates/Mon, 01 Jan 0001 00:00:00 +0000https://docs.whmcs.com/9-1/payments/tax-tutorials/update-tax-rates/Tax rate updates happen on the Tax Rules tab by deleting and recreating a rule with the new rate, or via SQL (UPDATE tbltax, UPDATE tblinvoices) on self-hosted installs, plus notes on rebilling fixed-amount PayPal or 2Checkout subscriptions after a change.