Customer's NS instance does not have SuiteTax installed (therefore using legacy tax). I'm attempted to create a vendorbill record using REST API, but I'm unable to set the tax code on the line item: "expense": { "items": [ { "department": { "id": "124" }, "account": { "id": "367" }, "amount": 100.00, "memo": "RS Test Invoice", "taxCode": { "id": "18" } } ] } But this results in 400 Bad Request: Error while accessing a resource. Please enter value(s) for: Tax Code.. Id is correct, it appears that I'm not able to set the tax code via REST API. Would a valid workaround be to create the vendorbill record via REST API without tax details, then use a custom restlet to add the tax details? Would this work, and any advice on how to construct restlet (e.g. what methods to use)?

"REST web services do not support legacy tax features. To work with taxation through REST web services, you must have the SuiteTax feature enabled. For more information about using SuiteTax, see SuiteTax." Not an option at this point for customer to enable SuiteTax, hence me looking for a workaround

you are failing to use an integration option that is explicitly not supported

maybe set the tax code via script instead beforeSubmit or something like that

thats not an option, missing mandatory fields means the record errors before reaching the user event

Could you add a default tax code value with Before Load, send the desired tax code in a custom field, and copy it over with an After Submit?

rather than hacky fragile workarounds, use SOAP. If you're allergic to SOAP, use a restlet and continue to speak JSON.