Automate Invoice Processing in Make: Scenario Walkthrough

Use one dedicated mailbox, such as an invoices address, so the trigger only sees invoices. Then build the chain in this order:

1. Trigger: watch the mailbox for new messages with attachments.
2. Filter: continue only if there is a PDF or image attachment, and stop otherwise.
3. Extract: send the attachment to a document-extraction service, or an AI extraction step, that returns vendor, invoice number, date, due date, total and line items as fields.
4. Validate: check that required fields exist and that the total is a number.
5. Match: look up the vendor in your approved vendor list and check whether the vendor and invoice number were processed before.
6. Route: send low-value, known-vendor invoices to draft-bill creation, and everything else to an approver.
7. Log: write the outcome, the source email and a link to the file to a sheet or board.

Build steps one to three first and confirm the extracted fields look right on ten real invoices before adding anything else.

Duplicate payment is the costliest failure in an AP automation. Create a duplicate key by joining the vendor name, invoice number and total, then store every key you've processed in a data store or sheet. Before creating a bill, search for the key. If it exists, stop and send the message to review with a note saying it looks like a duplicate.

Add validation checks that catch common extraction errors:

• The total should equal the sum of line items when line items are present.
• The invoice date shouldn't be in the future or more than a year old.
• The vendor must match your list, using a close match, not an exact one, to handle spelling differences.
• The currency should match what you expect for that vendor.

Anything failing a check should go to a person, not be quietly fixed. The point of validation is to route uncertain cases to review, not to guess.

Use a router with a path for each outcome. Define the paths in plain language first: for example, say invoices from known vendors under $500 create a draft bill automatically, invoices from known vendors above that go to the budget owner, and invoices from unknown vendors go to finance for vendor setup. Pick thresholds that match your own approval policy, and write them down first if you don't have an approval policy yet.

Send approval requests to a place where people already work, such as email with clear approve and reject links, or a board item. Log the approver and time in your record. Keep the accounting tool as the place where a bill becomes payable, and let the scenario create drafts only, so a human step always sits between extraction and money leaving.

Make scenarios stop when a module fails, so plan for failures deliberately. Add an error path to the extraction and accounting steps that sends the original email and the error message to a review queue and notifies a named person. Without it, a failed run just sits in a history log that nobody reads.

Test with unusual invoices: a scanned image, a multi-page PDF, a credit note, an invoice in another currency and an email with no attachment. Note which ones fail and whether they fail safely. Then run in shadow mode for two weeks, with the scenario creating drafts while your normal process continues, and compare results. Only switch over when the drafts match your manual entries.

Also watch the volume of operations the scenario uses against your plan, and confirm in your account what your plan includes rather than assuming.

Make suits visual, multi-step flows where you want to see branches and control error paths. If your flow is a simple two-step connection, a lighter tool may be quicker. If you need heavy governance, many users or complex approval chains, compare options in this automation platform comparison, and read when to move to an enterprise automation platform for signs you've outgrown a simple tool.

For the broader question of extraction quality and controls, see AI document processing for accounts payable. A board in an operations tool such as Monday.com can serve as the review queue where exceptions are assigned and tracked. Document the finished flow, using the approach in how to document processes and get out of founder bottleneck, so more than one person can maintain it.