How do you get the Purchase Order Number to print on the invoice to a client

Thanks for reaching out to the Community, J Beth Annon.
 

To show a custom field, like Purchase Order Number, on printed invoices, you'll need to turn on the custom field's Print on form option for invoices.
 

Here's how:
 

1. Use your Gear icon.
2. Go to All lists, then Custom Fields.
3. Find the Purchase Order Number custom field you're working with.
4. Click its Edit option.
5. If your Print on form for invoices is turned off, turn it on.
6. Select Save.
   
   

Now printed invoices will display the data entered in your Purchase Order Number custom field.


 

I've also included a detailed resource about working with custom fields which may come in handy moving forward: Add custom fields to sales forms & purchase orders
 

Please don't hesitate to send a reply if there's any additional questions. Have a lovely Monday!