HI Cristian!

There is no single best site. There are many sites and ways to save, depends on origin and destination. For expensive destinations its better to get professional help from flight experts.  Check this out https://www.facebook.com/flystein/

First, clear your Cookies. If you are researching a trip to New York City, for example, these travel sites will know you are looking to travel and increase your fare. I would try sites like hopper to help you gauge when to by tickets depending on your destination. 

I often use www.momondo.com for finding cheap tickets, but there are several good search engines for that.

I posted an article about the subject last week on my personal travel blog:http://travellingclaus.com/finding-cheap-plane-tickets/

Skyscanner is a fantastic fare compare site. www.makemytrip.com is also one I personally use that gives you great deals and has a user-friendly interface.

Hi Cristian. Finding deals on flights is always on the top of my travel checklist. Here are two websites that I recommend using: skyscanner.com & fly.com. Both sites save you time by searching through thousands of flight companies to find the cheapest option. Between the two I really like fly.com's calendar view because you can see the flight pricing for the whole month along with months before and in the future. You'll see what I mean when you actually go to fly.com website. Hopefully this was helpful and good luck on finding deals.

https://www.google.com/flights/ or the OnTheFly app

So far I have been able to get great deals from www.skyscanner.com it's great!!

I like Skyscanner, it compares a bunch of sites. If I notice a flight is all on the same carrier I will usually check through that carrier's site as well. Often times you can get a slightly better price o that way. If it's using multiple airlines then booking through a third party is going to better, though.

Hi, All the websites has the similarity of providing the service, costing etc. Also to compare many websites is tiresome.

The simple logic which I found is always use the local webiste of the particular country for more benifit in terms of costing, instead of visiting the mature websites.

I was able to find the variations but honestly it may not be in all the cases or destinations.

Kayak!

Try Skiplagged.com 

I like Skyscanner, Momondo and Expedia. If you are travelling in Europe always check the Ryanair website after midnight as some of the cheapie fares are dumped then.

I suggest Skyscanner

Bear in mind that many international tickets sold in Colombia do not have Carrier Imposed Fees (noted as YQ and YR surcharges). The same is true in Brazil. Of course the ticket must be issued in Colombia.

So if you were to use search engines for OTA outside Colombia, you might see a totally different fare structure.

The easy answer to your question is to simply search as many site as possible at the same time. No one source will win all the time.

http://www.skyscanner.com/ and http://www.momondo.com/ are great sites for reference but ALWAYS check the airline site before booking. At times I have found the same flight cheaper.

Hey Cristian, generally speaking Kayak is always delivering the best results for me, with one exception - one way tickets. If you want to book a one way ticket I always get the best prices on Cheap O Air. Another tip is to book your tickets on Tuesdays, the prices are always lower then. Cheers!

Adioso 

Momondo 

Matrix IT'S 

*the 3 best ever!!!!!!& I've researched all!

You should try Hipmunk, Jetblue and Despegar :)

Hi there. 

Logitravel/TopAtlântico and Momondo and sometimes directly with the airline, you may be surprised ;-)

I use Cheaptickets.com almost exclusively.

Hello Cristian, I usually use Momondo and skyscanner... I think they are the best to find the cheapiest air tickets.

http://www.cheapoair.co.uk/

lastminute.com

Sometime after midnight be ready to purchase cancellations

I always use skyscanner.com as it compares a lot of sites

From a comparison I made a while ago, the top 5 websites with the cheapest flights are (ordered by cheapest):

1. Momondo

2. Skyscanner

3. TripAdvisor Flights

4. Kayak

5. Hipmunk

Note that most budget airlines don't appear on flight search engines, so most of the time you have to manually enter their website and book directly from there. 

I wrote about this in detail in the complete guide for booking the cheapest flights

These days I mostly just use Momondo & Skyscanner as they're the ones that consistently result in the cheapest flights 99% of the times.

If you're not locked in on a specific destination - then check out Google Flights to help you find potential travel destinations that are within your budget and interests. Then once you find a destination you're interested in - use the flight search engines i listed above to find the cheapest flights (Google Flights is usually more expensive than the ones listed above)

Hi Christina,

I actually went to roundabout travel and got a really great deal.  Travelling from Australia to Europe in August this year with 2 stop overs as I really don't want to do the long trip in one go.  Stopping overnight in Singapore and then stopping in New York in the USA  for 9 days total price $1576 Bargain.  Just a shame that our Aussie dollar is struggling.