Hi there, @ConA. I'm here to help you record the owner's mileage in QuickBooks Desktop (QBDT).

Yes, you can record the owner's mileage with a journal entry in QBDT. Please note that mileage is not an accounting expense. This is a deduction for tax time that you can take if you don't get the actual costs of running the company car. 

To start creating a journal entry, I highly recommend reaching out to your accountant. This is to ensure you'll assign the transaction accurately and avoid messing up your books. If you're not affiliated with one, you can use our Find an Accountant tool to look for a Pro Advisor near you. 

For more information in tracking mileage in QBDT, please check this article: Set up mileage tracking in QuickBooks Desktop.

I'm always here ready to help if you have any other concerns about recording owner's mileage in QBDT. Have a good one and stay safe.