How do I creat an expense and detail with subcategory?

Creating expense with sub-category in QuickBooks Online (QBO) is pretty easy, frank. Let me walk you through how:

1. Click the + New button, then choose Expense.
2. Fill out the necessary information.
3. Under Category details section, click Category dropdown, then select + Add new if you don't have a sub-category.
4. Select the appropriate account and detail type, then enter the name.
5. Tick the Is sub-account check box, then pick a parent account and hit Save and Close.
6. From the Expense page, click Save and Close again.

In addition, if you plan to pay for the expense in the future, enter it as a bill: Manage bills in QBO.

We'll be on the lookout for your reply if you have further assistance managing your expense in QBO. Take care.