What 3-way matching is and why your finance team needs it
The term may sound like jargon, but the problem is universal: nobody should pay an invoice without checking what was ordered and what was received.
Quick answer
3-way matching (three-way reconciliation; in Spain, «triple conciliación» or «conciliación a tres bandas») is the control that compares each supplier invoice against two documents before its payment is approved: the purchase order (what was agreed) and the delivery note (what was received). If the three sources match line by line within a tolerance, the invoice is approved; if not, it is held with the discrepancy identified.
If you are the CFO
When manual ticking-off stops holding up and automating the control pays off.
AP lead
Which errors 3-way catches: overpricing, over-invoicing, invoice without a purchase order, duplicates.
Operations
The three legs —purchase order, delivery note, invoice— and the question each one answers.
The name sounds like jargon, but 3-way matching solves a very down-to-earth problem: not paying an invoice without checking what was ordered and what was received. It is the core of automated three-way reconciliation.
The three legs, in one table
| Document | What it represents | Question it answers |
|---|---|---|
| Purchase order (PO) | What was agreed | Did we order this, at this price? |
| Delivery note (GR) | What was received | Did it really arrive, in this quantity? |
| Invoice | What is charged | Are they charging us exactly that? |
What it catches (with examples)
- Overpricing: the purchase order said €100/unit and the invoice charges €104. A 4% that, multiplied by a year of purchases, is serious money.
- Quantity over-invoicing: an invoice for 110 units with a delivery note for 100. Without 3-way, it gets paid.
- Invoice without a purchase order: nobody authorised that purchase. The control stops it at the door.
- Goods not received: the invoice is on time, the delivery note does not exist. The case waits for the delivery, not the other way round.
- Duplicates: the same invoice through two channels (email and portal). The uniqueness check blocks it.
Why "line by line and before VAT" is not a technical detail
Comparing totals is the classic trap: two errors cancel each other out, mixed VAT rates muddy the numbers and a partial invoice never matches the purchase order total. Serious 3-way matching compares quantity and unit price PER LINE, at pre-tax prices, and applies the tolerance to each line (2% or €1.50 is a reasonable calibration). It is the difference between a real control and control theatre.
On each line, the control compares five things:
- Quantity: the invoiced quantity against the one received on the delivery note and the one ordered.
- Unit price: the invoiced price, before tax, against the purchase order price.
- Unit of measure: that box, kilo or unit mean the same thing in all three documents.
- Discounts and terms: that the agreed rebates and discounts have been applied.
- Taxes: the correct VAT rate per line (and Spanish IRPF withholding where it applies), even though the comparison is made on the pre-tax amount.
Does your 3-way matching compare totals or lines? ininvoice does it line by line, at prices before VAT and with a configurable tolerance, and holds whatever falls outside with its reason.
Want to match purchase order, delivery note and invoice today? The three-way matching Excel template does it line by line with formulas and tolerances; the three-way matching guide explains each step. Download the three-way matching template
What about 2-way and 4-way?
2-way (invoice against purchase order) is enough for services with no physical delivery. 4-way adds quality inspection as a fourth leg — common in pharmaceuticals and chemicals. Most SMEs with physical goods live in 3-way.
Doing it by hand vs. automating it
By hand: someone opens three PDFs, ticks off lines and decides. Sustainable up to ~50 invoices/month; after that, ticking off degenerates into "approving at a glance". Automated with ininvoice: invoices, purchase orders and delivery notes come in on their own from the mailbox, matching runs line by line with your tolerance, whatever matches is ready for a person to approve, and your team spends its time on the cases with a discrepancy, with the exact line flagged. Onboarding in 24-48 h.
Frequently asked questions
- Are 3-way matching and three-way reconciliation the same thing?
- Yes. It is the same control under its English and Spanish names («triple conciliación»). In Spain «conciliación a tres bandas» is also used.
- Does it work if my suppliers do not send a delivery note?
- For services, 2-way (invoice-purchase order) is the right control. For goods, it is worth requiring the delivery note: it is your proof of receipt.
- How many invoices justify automating it?
- When manual ticking-off starts skipping reviews — typically between 50 and 100 invoices/month — the cost of an error exceeds the cost of the tool.
Related content
Real 3-way matching, not control theatre
ininvoice compares line by line at prices before VAT with a configurable tolerance. Whatever matches is marked «matches», ready for a person to approve; whatever does not arrives flagged.