How to build three-way matching

What matters here

• Match at the line, not the total. Two wrong lines can add up to a right total.
• Ask the requester to confirm services were delivered. There is no delivery note for a consultant's week.
• Hold an invoice that arrives before its receipt, and release it the moment the receipt lands. Rejecting it annoys a supplier who did nothing wrong.
• Treat a price change as an exception, never a tolerance. That is a supplier changing terms.
• Measure the first-pass match rate. It tells you whether the tolerances or the receipts are the problem.

Who this is for

You run accounts payable or finance systems. Invoices are matched to the purchase order by eye, receipts are recorded when somebody remembers, and the exceptions queue is a shared inbox.

How it works in practice

What has to happen between a supplier's invoice arriving and it being cleared to pay.

1. 1

   The invoice is tied to its purchase order

   By the order number on the invoice, or by supplier, amount and open orders when the number is missing or wrong.

2. 2

   Each invoice line is matched to an order line and a receipt

   Quantity, unit price and amount compared line by line, with freight and tax handled as their own lines.

3. 3

   Differences inside tolerance clear on their own

   A small rounding difference or a quantity a few percent over, within limits finance sets per category.

4. 4

   An invoice ahead of its receipt waits, then releases

   Held rather than rejected, and cleared automatically when the receipt is recorded, usually a day or two later.

5. 5

   Everything else goes to a named person

   With the order, the receipt and the invoice side by side and the difference highlighted, not a line in a shared queue.

6. 6

   Cleared invoices go forward for payment

   On the supplier's terms, with the match result recorded against the invoice for the audit.

Paste these into Claude Code or Codex with the Tray Headless plugin installed. Each stage runs on its own. The systems named in them are the worked example rather than a requirement, and every prompt says so.

Once per project, run /tray-workflows:set-workspace to pick the workspace these build in. Point it at a sandbox first.

1. 1

   First, read how orders and receipts are held

   Matching is only as good as the receipt data under it.

   Headless skills build-workflow

   Copy

   Use build-workflow. The systems in play are Coupa, NetSuite, Slack,
   Okta and Snowflake, or whatever we run in those seats. Before you plan
   anything, tell me which of them are already authenticated in the
   workspace.
   
   I need the purchase order and its lines, the receipt and its lines, and
   the supplier invoice and its lines, in whichever system holds each.
   
   Then tell me: are services receipted at all today, or only goods. That
   answer decides how much of this is matching and how much is getting
   receipts recorded in the first place.

2. 2

   Match line by line

   Two wrong lines can add up to a right total.

   Headless skills build-workflow tray-gotchas

   Copy

   Use build-workflow and tray-gotchas. When an invoice is posted as a
   draft, tie it to its purchase order:
   
     By the order number on the invoice, if it is valid for that supplier
     Otherwise by supplier and open orders with enough remaining value
     Otherwise stop and route to AP, never guess between two orders
   
   Then match each invoice line to an order line and its received quantity:
   quantity, unit price and line amount. Treat freight, tax and discounts
   as their own lines, not as differences.
   
   Handle units explicitly. An order for 2 boxes of 50 and an invoice for
   100 units is a match.

3. 3

   Set tolerances finance can change

   So the small differences clear and the real ones stop.

   Copy

   Hold tolerances in a table, by category and optionally by supplier:
   
     price: a percentage and an absolute cap, whichever is smaller
     quantity: a percentage over, never under
     amount: a total cap on the invoice difference
   
   Inside every tolerance, clear the line. Outside any, stop.
   
   Always treat these as exceptions regardless of tolerance:
   
     A unit price different from the order on every line. That is a price
     change, and it needs the buyer.
     An invoice quantity above the ordered quantity in total.
     The same invoice number from the same supplier twice.

4. 4

   Hold invoices that are ahead of the receipt

   The goods are usually two days behind the paperwork.

   Copy

   When an invoice line has no receipt yet:
   
     For goods, hold the invoice and release it automatically when the
     receipt is recorded and the line matches.
     For services, message the requester in Slack: did this arrive, with
     the order line and the invoice amount, and buttons for yes, partly
     and no. Record their answer as the receipt.
   
   If a hold is still open after a number of days I set, remind the
   requester, then route to AP with the age shown.
   
   For a partial receipt, clear the matched quantity and keep the rest of
   the invoice on hold. Never clear the whole invoice for part of the goods.

5. 5

   Send every mismatch to a person, and report the rate

   A shared exceptions queue is where early payment discounts expire.

   Copy

   Every exception goes to one named person: the buyer for a price
   change, the requester for a receipt question, AP for anything else.
   Show the order line, the receipt and the invoice line side by side with
   the difference highlighted, in Slack, with the age of the invoice and
   any discount deadline.
   
   Report weekly: first-pass match rate, exceptions by reason and by age,
   invoices on hold waiting for a receipt, and discounts lost to an open
   exception.
   
   If most exceptions are missing receipts, the fix is receipting, not the
   tolerances.

6. 6

   Validate, then hand the tolerances to AP

   Because what counts as close enough is finance judgement.

   Copy

   Run the per-step schema checks and the whole-workflow audit before this
   touches production. Run it in report-only mode for one month end first,
   so the tolerances are set from real invoices.
   
   Then open the same workflow in Tray Build so accounts payable can change
   the tolerance table and the hold periods in the visual canvas.

What it connects to

The order and receipt live with procurement, the invoice and the payment with finance.

Named systems are the ones most teams run, not the only ones that work. Each is an authentication in your Tray workspace, referenced by name, so the workflow never holds a credential. Where we have a connector page, the name links to it.

Questions people ask

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