No PO, no pay: why enterprise customers park your invoice

Summary

• Large companies pay against a purchase order. Their accounts payable system matches the invoice to the PO before releasing any payment, so an invoice with no PO can’t be matched and gets held.
• The PO is usually held by a different person than the one who pays: procurement or the buyer raised it, accounts payable settles it. Chasing AP for a PO they don’t have wastes everyone’s time.
• Getting the PO right is slow because it crosses teams and systems, so it needs a head start.
• Start before the due date. A pre-due reminder that asks for or confirms the PO moves your invoice to the front of the queue while there’s still time to make the payment run.

What “no PO, no pay” actually means

Most small businesses invoice and get paid by the same person. Large companies don’t work that way. They separate who is allowed to commit the company to a cost from who releases the cash. The purchase order is the document that connects the two.

Before a supplier is engaged, someone raises a PO. That PO commits an approved budget to a specific spend. When your invoice arrives, accounts payable matches it against that PO, and often against a goods-received or service-received note too, in what’s called a two-way or three-way match. Only once the invoice, the PO and the receipt line up does payment get released.

If your invoice arrives with no PO number, or the wrong one, there’s nothing for the system to match it to so it gets set aside. In most AP systems this has a specific status: parked, on hold, or blocked. In other words, your invoice is stuck.

A parked invoice moves to the bottom of the priority list

A parked invoice can get forgotten for a few reasons:

• It’s silent. Many AP systems won’t notify you that an invoice is on hold. From your side it just looks unpaid.
• It’s nobody’s job to fix. The AP clerk can’t approve it without a PO and it’s often not their job to proactively find one for you.
• It can miss run after run. Payment runs only pick up matched invoices. A parked invoice is skipped every cycle until the PO appears, so it drifts from 30 days to 45 to 60.

Chasing this like an ordinary overdue invoice makes it worse. You send a firm reminder to accounts payable, but AP was never the blocker. The PO is missing and the person who can supply it sits in a different team.

Why getting a PO is slow

Getting a PO isn’t one email. It usually crosses two or three people:

1. Your contact realises a PO is needed and asks their internal buyer to raise one.
2. The buyer raises it in the company’s procurement system, which may need its own sign-off.
3. The PO number comes back to you, and only then can it go on the invoice.
4. You then need to resubmit the invoice with the PO to the Accounts Payable team.

Every one of those steps introduces delay which is why you need to get a headstart on tracking down that PO.

Kick off the process of getting a PO number before the due date

The fix is to start tracking down a PO number earlier. Start with a short, friendly note before the due date: here’s the invoice, please confirm the PO number so we can get it onto your next payment run.

Done a week or two ahead, this gives the customer time to raise or find the PO while there’s still time. Most corporate contacts are glad of the nudge, because a parked invoice is a headache on their side too.

This is the single strongest pattern we see in the data. 70% of the businesses with the highest collection rates on Trove use pre-due-date reminders. For corporate customers where a PO gates the whole payment, that head start is the difference between getting paid on terms and waiting for the run after next.

How Trove builds a system for finding PO numbers

Trove helps you build a system that means you never submit an invoice without a PO number on it. Here’s the process:

• Add whichever contact holds the PO number in Trove
• Set up a reminder in Trove to send to that person, 14 days before the invoice is due
• Once the PO number is in, Trove automatically adds it to the invoice and then sends the invoice to Accounts Payable
• If it’s still not paid after the due date, Trove starts sending chasers from your email address

If you’re not sure which contact holds the PO number, Trove will use AP at first. Usually, they will respond with the correct person to contact at which point Trove will email them instead.

This speeds up the process of getting your PO number in place and therefore getting your invoice paid on time.