Extract and post supplier invoices with AI, routing exceptions for review

## Extract, validate and post supplier invoices with AI and route exceptions for review Who it is for. Accounts payable teams receiving supplier invoices by email or upload. What it does - Extracts supplier, TRN, invoice number, date, subtotal, VAT, total and lines from the document. - Validates against the supplier master and open purchase orders: TRN format and match, duplicate number, lines add to subtotal, total equals subtotal plus VAT, extraction confidence, auto approve limit, supplier limit, PO match. - Routes by result: AUTO APPROVE posts the bill; REVIEW opens a ticket with the reasons; REJECT alerts accounts payable. - Every decision carries its rule code. Setup 1. Set base and the limits in Config, or replace the HTTP Request nodes with your document extraction, accounting and ticketing nodes. 2. Point your mailbox trigger or upload form at the Webhook URL. 3. Adjust the VAT rate and tolerances in the validation Code node. Activate. All external systems are reached through HTTP Request nodes against base in the Config node, so the whole flow imports and runs against any REST backend; swap any of them for the native n8n node of your system. Built and tested on sample data by Finamatik: https://finamatik.com/work/invoice-intake Requirements. n8n 1.100 or later; for the AI steps, a model endpoint at base/llm/complete or the OpenAI or Anthropic node in its place; your own systems reachable over HTTPS. How to customise. Every rule lives in one Code or Config node and is named for what it decides; change the thresholds there, not in the branches.