Last name first

There is no preference for automatically saving the name one way or the other.

Instead, the names will appear on the customer list based on how they're entered in the "Customer Name" field at the top of New/Edit Customer window.

Glad to see you in the Community, @Eaglelion. I'd be happy to assist you on how to make the Last name appear first before the first name in QuickBooks Desktop (QBDT).

The QBDT program has its latest update and this includes the changes on the Name as the default column. The option to make the Last name to be on the first column is unavailable.  No worries, you can customize the column order and show the Last name after the default ones. Then, you can sort it out to have a better view of the list of your customers. Let me show you the steps below:

1. Go to the Customers menu and choose Customer Center.
2. In the Customers & Jobs tab, right-click on any columns and select Customize Columns.
3. Locate Last Name and First Name in the Available columns section.
4. Select the Add button on every column you'd like to include.
5. In the Chosen Columns section, click on the column name and choose if you want to move it up or down by clicking on the Move Up and Move Down buttons.
6. Select OK.
7. To sort the last name from A-Z or the opposite, click on the LAST NAME header to do the work.

I've added some screenshots for your additional reference:

Now, every time you're going to sort the customer's last name, click on the LAST NAME column and it will sort automatically.

Moreover, you may want to check out this article to know more on how to track your business' status in the future: Understand reports.

I'll be around if you need further help with customizing the columns in the Customer & Jobs tab. I'll be one click away to assist you. Take care!