Custom List Import
CSV import is not supported for custom lists with more than 25,000 values.
A custom list is a list of values that can be used to populate dropdown lists on NetSuite forms. With the custom list import, you can import several custom lists together. You can use the Import Assistant to create new custom lists and update existing custom lists.
After you import a custom list, you can add it to a form by completing a few other steps: creating a custom field of type List/Record or Multiple Select, choosing the imported list as the List/Record value for the field, and adding the field to the form. You can add the custom field to multiple forms as needed. For more information, see Custom Lists and Creating a Custom Field.
To import custom lists, select Customization as the import type, and Custom List as the record type.
Review the following guidelines for more details about custom list imports:
The Import Assistant is available at Setup > Import/Export > Import Tasks > Import CSV Records. After you select the record type for import, you choose the import character encoding. For more information, see Select a Record Type for Import and Choose Import Character Encoding.The rest of the steps are like with any other import.