Invoice sent_at Field
April 30th, 2026
The Invoice resource now includes a sent_at field on V3 endpoints, recording the timestamp an invoice was first sent to the customer from Rillet. The field is intended for downstream systems — particularly tax platforms — that need a precise, legally binding date for tax registration and similar compliance workflows.
sent_at is set the first time the invoice is sent and does not change on subsequent sends. It is null for invoices that have never been sent from Rillet, and is not populated by preview emails or payment reminders.
Available on all V3 endpoints that return an Invoice resource and on the invoice-updated webhook event.