TULSA, Okla. -- Through Aug. 31, Thrifty's online summer sweepstakes will award 85 daily prizes of a free week of car rental in the U.S.

"Summer is a time for our customers to kick back, relax and enjoy their free time," said Brian Carpenter, vice president of sales, marketing and advertising. "We thought we'd make it that much easier by giving away a free week of car rental to 85 lucky travelers."

No purchase is required to enter the sweepstakes, but winners must be a U.S. resident at least 21, have a valid U.S. driver's license, and meet certain car rental requirements.

Winners of the 85 daily prizes will be randomly drawn from among all entries received by 5 p.m. CDT that day. Non-winning entries remain eligible for future drawings. Each daily winner will receive one free week of car rental in the U.S., including economy, compact, mid-size, full size or minivan, subject to availability.

All taxes, fuel, optional insurance coverage and any other incidental charges are the sole responsibility of the winner. Winners must possess a credit card in their own name. Entries are limited to one per person. Additional details about the contest are available online at www.thrifty.com .