Hi @deangorton,
I believe you're referring to the custom fields for QuickBooks Online (QBO) Advanced.
This feature is found in this article: Create and edit custom fields in QuickBooks Online Advanced. At this time, this specific version of QBO is exclusive to the USA. An estimated time as to when it will be released to other regions is also unavailable.
I suggest you keep an eye out on this page: The QuickBooks Blog. It lists new features that are out each month, along with its short description.
If you have other questions about the QBO product, let me know in the comments below. I'll be sure to take care of them.
