As the adage goes, nothing in life is free. But my experience purchasing a flight with a Capital One Venture X Rewards Credit Card on the issuer’s travel portal is about as close as it gets.In this case, it was Capital One’s automatic price drop protection benefit — through the Capital One Travel portal — that provided an unexpected partial refund. Even better, since I booked the flight using the Venture X card’s up to $300 annual portal statement credit, I got the refund in the form of, well, even more statement credit.For more TPG news, deals and reviews delivered to your inbox, sign up for our daily newsletter.The Venture X card, a 2021 TPG Award winner for best new card, has a lot already going for it. Besides the aforementioned $300 credit, cardholders also receive 10,000 bonus miles each year they hold the card, Priority Pass and Capital One Lounge access, various travel and purchase protection benefits and more.Here’s how the recently relaunched Capital One Travel portal got me “free money.” (Well, as close as it gets to free.)Booking a flight through the portal(Screenshot from Capital One)First, to access the Capital One Travel portal, you’ll need to have one of the following cards:Capital One Venture Rewards Credit Card.Capital One VentureOne Rewards Credit Card.Capital One Venture X Rewards Credit Card.Capital One Spark Miles for Business.Capital One Spark Miles Select for Business.Capital One Walmart Rewards® Mastercard®.The information for the Capital One Spark Miles Select and Capital One Walmart card has been collected independently by The Points Guy. The card details on this page have not been reviewed or provided by the card issuer.When you’re searching for a flight – as I was – the portal may recommend that you purchase immediately.Essentially, the platform is predicting that airfare prices will increase in the future and suggesting that you lock in the lower price now. In fact, Capital One (in partnership with travel technology company Hopper) is so confident in its algorithm, that it will automatically apply price drop protection to that particular purchase.Sign up for our daily newsletterEmail addressSign upI would like to subscribe to The Points Guy newsletters and special email promotions. The Points Guy will not share or sell your email. See privacy policy.What exactly is Price Drop Protection?(Screenshot from Capital One)Here’s how it works: Capital One will monitor the price of the flight after you buy it. If the price drops, you’ll get a refund for the difference in price to your original payment method.The terms of the price drop protection can change based on your exact itinerary and dates. But once price drop protection is applied to a flight, Capital One Travel will monitor the price of that particular itinerary (with the same flight and fare class) for a set amount of time after purchasing.How Price Drop Protection worked in practiceAbout three weeks prior to a trip to Chile, I used my Venture X card to purchase a one-way flight from Punta Arenas (PUQ) to Santiago (SCL) on the issuer’s travel portal. As mentioned, Capital One’s algorithm recommended that I purchase the flight immediately, as it was looking like flight prices would increase.The total purchase price was $81.36 and I received 5 miles per dollar for this booking (yes, you still earn Capital One miles even when using the $300 statement credit).(Screenshot from Capital One)Several days later, I noticed an email from Capital One with a subject line that said, “Good news! You’re getting a refund.“Since I couldn’t recall returning anything that I had purchased with my Venture X, I was particularly interested in seeing what this was about. Lo and behold, the price of my domestic Chile flight had decreased — and Capital One was providing me with an automatic refund of $16.49.(Screenshot from Capital One)That’s almost 20% off my original flight cost, without me having to do anything at all. Color me impressed since it wasn’t something that I had expected.Bottom lineWhile I wouldn’t typically book travel through a third party, Capital One’s Price Drop Protection has me seriously reconsidering that approach. Pairing that with the $300 annual credit on the portal with the Venture X — and the ability to earn up to 10 miles per dollar on hotels or 5 miles per dollar on flights through the Capital One Travel — Capital One is making a compelling case for its own portal.The Capital One Travel portal, at least in its current iteration, isn’t perfect — there are a lot of basic filters and search results missing. But the issuer has said that improvements are coming and I can’t wait to see what they are.Official application link: Capital One Venture X with 75,000 bonus miles when you spend $4,000 on purchases in the first three months from account opening.