Hi Netsuite family! I have a question that has to do with custom segments vs custom field/list. On a sample bill JSON, does a custom segment look any different than a custom field /list?

yes, custom segment starts with cseg while custom fields start with custbody and custcol

okay other than the name of the "field" is the structure of the schema any different?

To the normal user, they will be the same.

Custom segments are available in Financial Reports as additional segments (like Subsidiary, Departments, class and locations). So it is mostly for Reporting Purpose. If that is not the requirement, I would suggest sticking with a custom field.