I did a search online and found this:
https://www.nationalcar.com/en/suppo...iver-fees.html
It seems clear that there is no fee, and even though I live in Illinois (on the special state list!), it seems it should be okay, but not totally sure!
Is there a fee for an additional driver?
Yes, there is a daily additional driver fee. This fee will vary and currently averages $12 a day.
The additional driver fee will be waived for any of the following types of rentals:
- Rentals in states that allow a renter's spouse to be an "Automatic" Authorized Driver: California, Illinois, Missouri, Nevada, Oregon, and Wisconsin.
- Rentals by Emerald Club members when the member's spouse, common law spouse, or same-sex domestic partner has the same address on the driver's license as the Emerald Club member and meets normal renter requirements.
- Rentals by Emerald Club members when the member's immediate family member (mother, father, son, daughter, brother or sister) has the same address on the driver's license as the Emerald Club member and meets normal renter requirements.
- Commercial (corporate) rentals when the renter's business partner, employer or fellow associate, who has an assigned corporate contract with National and drives the car for business purposes and meet normal renter requirements.
- Rentals for/by disabled renters who cannot drive (one additional driver fee will be waived)
EMC numbers can only be used when the actual member is picking up the vehicle. EMC status is not transferable and the reservation must be booked in the customer's name who will be picking up the vehicle and presenting the form of payment.
ALL ADDITIONAL DRIVERS MUST:
- meet all age requirements
- appear at the rental counter with the primary renter
- present a valid driver's license
An additional daily fee may apply for any Additional Drivers.
Note: State law in California, Illinois, Missouri, Nevada, Oregon and
Wisconsin allows a spouse to be an
automatic authorized driver as long as renter qualifications are met.