Locate the phone number of the rental location on your rental contract. You will need to contact the location you rented your car from directly, if the request is made during operating hours. If it is after hours, contact the customer service number on your rental contract. These can usually be found at the top of your rental agreement or directly on the keys to the vehicle.
Give the agent your rental agreement number and tell her how long you will be needing to extend the rental. She will tell you if this is possible depending on the availability of the vehicle. If not, she may offer you the opportunity to trade out your rental vehicle for a vehicle that has not been reserved for that time.
Agree to the new fees. When extending your rental contract, you will be responsible for additional daily fees. This may even change the original rate you agreed to, depending on the rental company. They may also add an additional hold amount on your debit or credit card to cover the additional fees.
Return the rental car at the agreed upon time. Keeping the car beyond this time can cause you to accrue additional fees. Most rental companies will charge additional hourly fees, a service fee, and a late day fee if the car is not returned by the time stated on the agreement.
