Don't you love summer? Airlines and hotels do too. When everyone wants to travel, everyone pays more for travel, it's as simple as supply and demand. Though you may see plenty of advertisements claiming "summer sale fares" compared to yearly averages, most things on offer are hardly "sales". If you play your cards right and exploit a few of the best weeks, you may just be able to grab a nice vacation without being fully gouged.
I've spent a couple of weeks searching popular summer routes like US to Europe, Europe to US, East Coast USA to West Coast USA, US to Hawaii, Intra Europe, Intra USA and vice versa for all. For the best current rates, the common theme seems to be go early or go late. Almost uniformly all the best rates I have seen are from late May to early June or late August to early September, with international tickets saving on average $200 USD during those times. If you have a trip in mind, I highly recommend using the ITA Matrix (desktop) to comb one month at a time to find your personal lowest fares.
Though there are endless theories on "when to book", there is no guaranteed time or method for success. DO however try to avoid last minute booking. Booking within 14 days rarely are the best fares, regardless of destination. Generally, you will do best by playing with options such as which day of the week to leave and return, as well as whether or not you are staying for a minimum number of days qualifying for a special air fare class or hotel discount. If you can couple flexible departure days with travel in the beginning or end of summer, I all but guarantee you will save worthwhile money.
Last summer, fares were exactly where they are now and I found that many (especially transatlantic) flights dropped precipitously as summer began to actually approach. It's all about comfort and flexibility and I find that airlines take advantage of those who need to lock in very specific mid summer dates (damn weddings). The way I see it, if the fares you want are shockingly high right now, I can't imagine them getting much worse, but they could get much better. I have been comfortable rolling the dice and it saved me about $325 per ticket last year booking in June rather than April/May for an August ticket. I cannot guarantee the same, but if you have comfort and flexibility you can always try. Sales are sporadic, competition arises and things happen. Lock in whatever you feel comfortable with, but be sure to play around with as many flexible options as possible before you do. Of course, I would always recommend grabbing these New York to Paris business class flights for less than coach is currently going for! No brainer!
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