Ultimate 2015 summer vacation travel planner

Best Tips for Summer Travel and Fun
Best Tips for Summer Travel and Fun

It's time to talk summer vacation. We caught up with travel experts from travel planning and booking sites Hipmunk, Kayak, Hopper, Booking.com, Orbitz and HomeAway to see what's the best time to book summer travel, when's the best time to travel and what are the hottest places to go this year.

Best time to book summer travel?

The data show the best time to book a summer vacation is about 90 days before you travel. Hipmunk says that's when U.S. flight prices are lowest, except for Fourth of July weekend -- if you're traveling then you should book about four months in advance. If you're booking an international flight, you need more time -- both Hipmunk and Kayak say booking six months in advance is best for destinations like Europe. (Though Kayak notes that Caribbean travelers can see the best prices two to four weeks out this summer.)

HomeAway says that booking a vacation rental 90 days before you travel is best, however 70 percent of owners say that they'll reduce rates if a place isn't booked four weeks out.

But don't panic if you haven't booked an early summer trip yet. Kayak trends show that U.S. travelers can find some of the best domestic deals four to six weeks before their trip.

Also, just because three months out is considered by many to be the ideal time to buy, that doesn't mean it's when travelers are actually booking their travel. HomeAway stats show that one third of U.S. travelers plan their trips about a month in advance. But keep in mind that last minute planning isn't always going to save you money. Hopper data suggests that airfares can rise $150 in the last four weeks before departure.

When to travel this summer?

According to Orbitz, the least expensive month for summer travel is August (based on average hotel prices). In fact, the data show that the cheapest week to travel this summer is August 24-30. If you can't take August off, consider the first week in June or the week after the Fourth of July -- those are the least expensive weeks in June and July, according to Orbitz.

Hopper breaks their flight data down even more, with this figure detailing which days are the most popular for U.S. travel, and when you'll see the best prices:

Keep in mind that the day you travel will also affect prices. Kayak says that for U.S. travel, returning home on Sundays will cost much more than if you extend your trip one more day and come home on Monday, after the weekend rush. If you're traveling to Europe, try depart on a Wednesday and return on a Tuesday.

Where to travel this summer?

When it comes to summer travel destinations, some will perpetually be at the top of the list. Booking.com numbers from last summer shows Paris, London, Rome, Niagara Falls and Barcelona as the top five most booked destinations by American travelers. Kayak's data for European travel this summer is similar -- the top five spots in Europe are Paris, Rome, Dublin, Barcelona and Athens. A weakened euro and cheaper gas prices mean this summer is an especially great time to visit Europe.

But there are some lesser-frequented destinations that are heating up this summer, according to Kayak. Kona, on Hawaii, the Big Island, has seen almost a 50-percent increase in interest among travelers this summer. Other trending places include Toronto, Hyderabad, Milan, Vancouver, Reykjavik, Calgary, Copenhagen, Edinburgh and Madrid.

But not everyone's escaping overseas. HomeAway's summer bookings see popular beach spots rise among vacation home renters, including the Outer Banks; Ocean City, Maryland; Myrtle Beach; Destin, Florida; and Cape Cod topping the list.

Related: Top 25 travel destinations for 2015

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