How to get a free upgrade A kind gesture and a smile can go a long way, especially when gate agents have to deal with difficult passengers on a daily basis. About 95% of those in first class on domestic flights last year were upgraded It's not unusual to see a first-class passenger give up his or her seat for military personnel Book directly with a hotel rather than a third party to help your chances of an upgrade (Budget Travel) -- If you want to score a gratis first class seat, swanky suite or high-end rental car, you can't rely on luck alone. Here are a few easy ways to improve your chances and upgrade your experience. I have a long, transcontinental flight coming up. I dread being cramped in a coach seat, but I can't afford first class. What are my chances of getting bumped up for free? They're actually better now than ever. To cut costs, some U.S. airlines have been offering fewer flights in recent years, and coach can be overbooked. If a carrier bumps passengers, it's frequently required to provide either a substitute flight or a refund or both, per government regulations. The airline may not want to bump people if first class seats are available. So how do carriers select the lucky few who get ferried to first class? It's all about the miles. Computers track frequent flier and program miles and upgrade passengers automatically, based on who has earned the most. About 95% of those in first class on domestic flights last year were upgraded or used frequent flier miles (sometimes with an additional fee), according to Joel Widzer, author of "The Penny Pincher's Passport to Luxury Travel." But you need a lot of miles to qualify: Delta requires you to fly at least 25,000 a year to qualify for its Silver Medallion level. On the other hand, you can sometimes find upgrade certificates for sale online, courtesy of frequent fliers who can't use them before their expiration date. For instance, some United/Continental vouchers on eBay start with bids as low as $1. But even if you don't travel often, simply being a member of the airline's frequent flier program helps your chances. It indicates some level of brand loyalty. Having an airline-sponsored credit card in your name helps, too, though those may come with hefty annual fees. Does dressing up so that you look like you'd belong in first class improve your chances of getting upgraded? Looking polished helps, but not as much as it once did. There's one outfit that seems to work better than even the finest couture: a military uniform. In the past few years, it's not unusual to see a first class passenger give up his or her seat for military personnel. Any other tips for flights? Remember that gate agents deal with a lot of demanding, obnoxious passengers, and offering a few kind words and a smile goes a long way. John E. DiScala, founder of travel advice site johnnyjet.com, reveals that chocolate helps him get upgraded -- or at least moved to a better coach seat -- about half the time. DiScala says he brings one-pound chocolate bars for the gate agents and flight crew, who have discretion on seating after the cabin door closes. Some people swear by the sob- or celebration-story strategy. Personally, I wouldn't go this route unless you really are a newlywed, on your way to a funeral, etc. Karma, you know. Showing up late might work, but it's risky. A man sitting next to me once in business class on Air New Zealand was huffing and puffing -- he confessed to being intentionally late for every international flight, because then they rush you on the plane and into any available seat. Of course, the downside is you'll be turned away if the flight is already full. One big upgrade advantage is flying solo. Airlines try to put families together, and they may need your coach seat to do that. Chances are there's only one empty seat in first or business class. Finally, before you book the flight, you may want to consider trading in your frequent flier miles for an upgrade, though the numbers may be steep: On Delta, it takes 10,000 miles for an upgrade on domestic round-trip tickets and 30,000 miles for flights from the U.S. to Europe -- but that's not applicable on certain discount fares. That said, there are more opportunities now than ever to earn frequent flier miles, not only by traveling but also through credit cards, hotel stays, car rentals and online shopping sites. "When you consider that one can earn three points per $1 spent on a credit card, 10,000 miles seems less daunting," Widzer points out. A friend of mine ended up getting upgraded to a suite at a hotel in Vegas. She's not a high roller, so how did she land that freebie? Just as with airlines, brand loyalty really helps. If you're visiting a chain hotel, sign up for its frequent traveler program. Also, according to Widzer, you're more likely to get upgraded if you book directly with the property, on the hotel's website or by phone, rather than with a third party, such as hotels.com. "Booking direct is by far the biggest thing you can do to get an upgrade," Widzer advises. If you see a lower price online, call the hotel and ask them to match it. Unlike with the airlines, however, you are most likely to get a hotel upgrade if you travel during a low-occupancy time, such as weekends at business-oriented hotels. When vacant suites are available, the hotel may bump you up, hoping to impress you and gain future business. You also may have better luck at a new property that's angling to create good word of mouth. The time of day matters, too. It helps to check in later, once the hotel has a better handle on its occupancy for the night. If you arrive at 8 p.m. and their suites still aren't full, they may upgrade you for free or for very little, since few new guests are likely to come and pay for them. Another strategy DiScala says has worked for him: Befriend the bellman. "I visited Vegas at a not-busy time once and tipped the bellman well," he says, "so he gave me a free upgrade." The same tactic may work with the concierge. Budget Travel: Secrets to the 10 most popular cruise ports What about rental cars? Is it true you're most likely to get upgraded if you book the cheapest car at first? Yes, and here's why: The cheapest rental cars tend to sell out first, leaving the company no choice but to upgrade you. That said, the check-in clerk may try to sell you an upgrade for a discounted fee. Say no. If they don't have the car you reserved, they usually give you a better model at no extra charge. Arrive early in the day, before most people return their cars, for the best shot. Loyalty also counts. Join a car rental company's membership program, and you may get special offers for upgrades. You should also search online for coupons. The site carrentalupgrade.com is worth bookmarking, in particular. Some car rental firms also run their own promotions for upgrades through organizations such as AARP and AAA. And always remember to ask; politely requesting an upgrade is often the best, easiest bet. Budget Travel readers' best upgrade strategies Volunteer to get bumped: My flight from JFK to Amsterdam was overbooked and someone was in my seat. He was adamant: He wouldn't move. I was so embarrassed by his behavior that I told the flight attendant if I could catch my plane from Amsterdam to Glasgow, I'd be OK getting bumped. After 15 minutes she said "follow me" and turned up a flight of stairs. I had never even seen first class before! -- Cyndi Armstrong, South St. Paul, Minnesota Speak in romance language: My hubby and I got upgraded to business class to Ireland for our honeymoon. We just mentioned the purpose of the trip during check-in and the flight attendant did it -- no questions asked. Another time, we got upgraded to a suite at a Crowne Plaza because we mentioned we were there for Valentine's Day. It was a nice surprise, since we'd scored the hotel on Priceline for a song. -- Caroline Dover Wilson, Greer, South Carolina Rent cars at the end of the week: Most compact and midsize cars are rented out early in the week to business travelers, so if you try to rent closer to the weekend, you have a good chance of getting upgraded because they are out of "business" cars by then. -- Megan Cushman Dezendegui, Miami What are your best strategies for scoring upgrades? Share them in the comments section below. Budget Travel: 15 international food etiquette rules that might surprise you