Hi there @lisa94! Welcome to the community. Not to worry, I'm sure we can get you squared away. When you integrate, TSheets will import all active customers in QuickBooks. To determine the best next steps, can you give me a few more details on your situation? Are you only tracking time for a few, but not all of your customers? Is deactivating them in QuickBooks an option? This will be the most effective way to make sure QB and TSheets are aligned. 

If not, I would recommend un-assigning any customers that you do not wish employees to see in TSheets. When a customer isn't assigned to any employees, it will not appear as an option when clocking in or out. Only you as the admin will be able to see them in TSheets. You can do that in the following way: 

1. Go to Customers.
2. Select .
3. To unassign, uncheck Assign to all team members, or select Edit to deselect all the boxes. Then go back and Save.

I do also want to be sympathetic to how many jobs you have, so if this is unfeasible in any way, let me know and we can figure out something together.