VAT Sentinel

The most common reason: your store uses the legacy classic (shortcode) checkout. The field is registered through the WooCommerce Additional Checkout Fields API, which renders on the block checkout (the WooCommerce default) — it does not appear on the classic checkout. Beyond that, the field appears when the cart is taxable, and it requires WooCommerce 8.9 or newer. If another plugin replaces or heavily customizes your checkout, the field may not render there.

Reverse charge only applies to cross-border EU B2B sales: the buyer's billing country must be an EU country different from your store's base country. A domestic order keeps VAT even with a valid VAT number. And if VIES was unreachable at the time, the default safe mode keeps VAT charged (see below).

By default (safe mode) the order is still accepted, VAT is charged, and the order is flagged "VAT pending verification" with a manual re-check button for when VIES recovers. There is an opt-in setting to apply reverse charge provisionally instead, clearly marked "at your own risk". Either way your checkout never breaks because VIES is down.

The VIES service was unavailable when the order was placed, so we accepted the order rather than blocking your sale and flagged it for re-checking. Until VIES confirms the number, the VAT treatment on this order is provisional and may be adjusted. VAT Sentinel records the check; it does not certify the order's tax treatment. Use the re-check button once VIES is back up.

Open the VAT Sentinel status panel; it shows live per-country availability straight from VIES.

No. Some EU member states do not return the trader's name or address (Germany, for example). The validity result and the consultation reference still stand; the log shows "not provided by VIES" for those fields.

No. It validates the number, adjusts the order's VAT via the standard WooCommerce exemption, and writes an internal order note plus an audit record. It does not generate or modify invoices, and it does not add reverse-charge wording to invoice documents — your invoicing plugin or accounting tool must do that.

In your own WordPress database: an append-only audit table (wp_vatsentinel_vat_log, with your table prefix) plus meta fields on each order. Nothing is sent to the plugin author.

Enter your own business VAT number in VAT Sentinel's settings. Validations are then made with your number as the requester, and VIES returns an official consultation number that is stored with the check — dated evidence that the validation was performed. Without your merchant VAT number configured, checks still work but VIES does not issue a consultation number.

Uninstalling removes the plugin's settings but deliberately keeps the audit table and order data, because validation records are tax evidence you are commonly required to retain for years. If you truly want them gone, remove the wp_vatsentinel_vat_log table and the order meta manually.

Use one VAT validation plugin at a time. Two plugins that both set the customer's VAT exemption will fight each other and can produce wrong totals. General tax-rate plugins are fine; a second VIES/VAT-number plugin is not.

No. VAT Sentinel validates numbers and keeps proof that you checked. It is not tax advice and does not guarantee compliance. Consult your tax advisor.