How to Put a Customer's PO Number on a QuickBooks Online Invoice

Large clients often refuse to pay an invoice until it quotes their purchase order number. The standard QuickBooks Online invoice has no dedicated box for one, and that gap sits behind one of the most common questions we hear from businesses billing corporate and public-sector work. Two workarounds cover almost every situation. The better of the two takes about two minutes to set up.

Why do customers insist on a PO number?

Most buying organisations run three-way matching. They compare the purchase order, the delivery record, and the invoice before releasing payment. An invoice with no PO number on it sits in their accounts payable queue, however correct the totals are. Printing the number is not a courtesy. It is how you get paid on time.

Does QuickBooks Online have a PO number field on invoices?

The standard sales form does not. QuickBooks Desktop has a P.O. number field on its invoice template, so people moving from Desktop are often surprised. In QuickBooks Online, the number has to travel in a field you repurpose: a custom field, the message box, or the memo. The custom field is the cleanest option, so start there.

Adding a PO number as a custom field

1. Open the gear menu and choose Custom fields. On older versions, the setting sits under Account and settings, on the Sales tab, inside Sales form content.
2. Create a field and name it exactly what the customer expects to see, such as PO Number or Customer PO.
3. Switch on printing, and tick the sales forms it should appear on: invoices, estimates, sales receipts.
4. Open an invoice, type the customer’s PO into the new box, and preview the form before you send it.

QuickBooks Online allows only a handful of custom fields on sales forms, and the exact number depends on your plan. If yours are already taken by job numbers or retainer references, one dependable workaround remains.

What if every custom field slot is taken?

The message box at the foot of the invoice is the best fallback. Type something plain there, such as PO: 4471, and it prints on both the PDF and the emailed form. The memo is a weaker carrier, because it is largely for your own records and many templates do not print it. Avoid stitching the PO onto the invoice number itself. It breaks numeric sorting and can confuse payment matching later.

Will QuickBooks Online fill the number in for you?

No. There is nowhere on the customer record to store a standing PO, and nothing copies one across from an attached document or an estimate. Someone has to type it, every time. The partial exception is the recurring invoice: the custom field is saved with the recurring template, so an unchanging monthly PO needs entering only once.

Test the setup before the next billing run

Add the field, put a real PO on one invoice, and email the PDF to yourself. If the number lands where an accounts payable clerk will look for it, make the entry part of raising the invoice rather than a fix afterwards. A few minutes of setup removes a common cause of slow payment.