MCLEAN, Va., Aug. 9, 2012 /PRNewswire/ -- The Capital One (NYSE: COF) Rewards Barometer ( www.capitalone.com) today revealed that while 33 percent of rewards card holders reported this May they would use rewards for summer vacations, only 21 percent redeemed. According to the barometer, a quarterly survey among American consumers that focuses on how they accumulate and redeem credit card rewards, the top barrier preventing customers from using their rewards points for travel was not having enough rewards to book the trip they wanted (43 percent). Blackout dates and lack of availability also prevented cardholders from redeeming their rewards for travel. "Card holders should understand that sometimes it can be difficult to use the rewards they've earned with some programs," said Amy Lenander, Vice President of Rewards Programs at Capital One. "At Capital One, we design our rewards programs to offer great value, flexibility and ease of use. For example, our travel rewards customers can redeem their miles for any travel purchase, even if it's booked at the last minute." Understanding Extra Fees When card holders redeem rewards for travel, their trip is not always as "free" as expected since they are sometimes charged extra for airline taxes, fuel surcharges, and booking fees when they redeem. According to the barometer, 37 percent of cardholders who used rewards for travel had to pay fees this summer when they redeemed their rewards. That said, more than one-third of respondents surveyed are not sure if they are charged a fee or additional expense when using rewards to book travel. Not only are card holders often unaware of the extra fees charged for rewards redemption, but more than half of the respondents (52 percent) are not sure if they are charged foreign transaction fees on their credit card purchases while traveling abroad.