The customer level mileage reimbursement rate lets you set a uniform reimbursement rate across all of your employees and vendors. Any mileage invoice item submitted will be calculated with the Mileage Rate entered on the Customer Settings page - unless they have a mileage reimbursement override.
The mileage rate is not required, but the mileage button will not be displayed on the Edit Invoice page if left empty.
1. Click on the Username Dropdown and then Customer Settings
2. Enter Mileage Rate (this value is measured in cents per mile)