We do our AP bill runs through Transactions → Payables → Pay Bills, then print from the Print Checks page with Check Type = Voucher. Here's the weird part: the voucher PDF that prints seems to depend on the Class on the underlying vendor bill. When the bill's Class is one specific value, we get the correct voucher. With any other Class, it prints a different (wrong) voucher layout. Same bank account, same Check Type = Voucher, the only thing that changed is the Class. I've already poked around SuiteAnswers (no luck), the bank account's check layout, and the Pay Bills / Print Checks form, but I can't find what's making it behave differently per Class. So my question: where does NetSuite tie the voucher print template to the transaction's Class? Would love a pointer to wherever that selection actually lives.

I presume you are using advanced PDF templates?

Yes, and I've checked that all my roles have the same default form for checks.

download the template and review the code. You might have a custom template with some conditional layout

I’m not aware of any native Class-to-voucher-template mapping in NetSuite. The printed check layout is normally determined by the Custom Form stored on the Bill Payment/Check record. That form then points to either an Advanced PDF/HTML Print Template or a basic PDF Layout. Oracle specifically recommends checking the Custom Form field on the check record to identify the layout being used.