To add a CDP (Counter Discount Program) number to your Hertz reservation, you can do so either during the initial booking process or by saving it to your permanent "Gold Plus Rewards" profile. On the Hertz website or mobile app, look for the box labeled "Discount/CDP/Club Code" in the initial search bar where you select your dates and location. Entering the code here will automatically apply the discounted rate to the quotes you see. If you are already a Gold Plus Rewards member, it is much more efficient to log in, go to "My Profile," and add the CDP under the "Membership & Payment" section. This ensures the discount—whether it’s from your employer, AAA, or a credit card benefit—is applied automatically to every future booking. In 2026, Hertz also allows you to add these codes during the "Check-In" phase of the app if you forgot to do so earlier, provided you haven't already prepaid for a non-refundable "Pay Now" rate.