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• A virtual private network (VPN) protects your online privacy and security through a secure server.
• Some people also believe flights can be cheaper if you use a VPN. Here's what our research found.
• To get the best flight prices, consider flying mid-week or traveling to and from another airport.

There are countless rumors on social media about the best ways to book flights for less. With the winter holidays approaching in the Northern Hemisphere, you can be sure that the more persistent among them will pop up in your feeds.

In particular, someone may tell you that the trick to finding cheap airfare is to use a VPN when you book. On the face of it, this makes sense. A VPN, or virtual private network, encrypts your data and masks your IP address, which ties your internet connection to a specific location. By using a VPN, you can appear to be in a different country from where you actually are.   

Why and when should you use a VPN?

A VPN is great for eluding government censors, keeping safe from eavesdroppers, and viewing or streaming content from locations where it would be blocked. But would appearing to be in a different country result in cheaper airfare?

We tested the premise against five of the best VPNs, and the results are pretty unequivocal: Flights aren't cheaper when you shop through a VPN.

Are flights cheaper with a VPN? 

The results are straightforward: No, flights are not cheaper with a VPN. Using several VPNs did not result in a single cent of difference in our test. 

But that does not mean that there aren't ways to find cheaper airfare. It just takes some flexibility. 

Travel tips for cheap flights

Travel mid-week

For example, you can look for flights in the middle of the week, when fewer businesspeople travel and demand is often lower. Studies show the cheapest day to fly is Wednesday, and the most expensive Sunday.    

Avoid last-minute travel

Booking in advance is a good idea, although you don't have to buy tickets months before flying.

Try to book at least 21 days before departure; prices rarely go down after that window.    

Consider traveling from a different airport

If you are based somewhere with access to multiple airports, you can also expand your search to more than one airport. Google Flights makes this easy by allowing you to search for flights from a given city rather than a single airport. If you look up flights from New York City, for example, the site will show results including all three main airports — JFK, LaGuardia, and Newark. Prices can differ significantly among them. 

What influences the price of flights?

There are still misconceptions about some other hacks that can get you cheaper airfare. Unfortunately, they don't work, and here's why.   

Using your browser in incognito mode

Websites track your online habits, so why wouldn't airlines tailor their prices to what they know about you? Airfare indeed fluctuates, but it does so according to factors that have nothing to do with your digital identity.   

Pricing is determined by algorithms based largely on demand. You won't defeat those algorithms by masking your identity with incognito mode, any more than you would by masking your location with a VPN.    

Booking on Tuesdays 

There's an old adage that booking on a Tuesday gives you lower prices. This may have been true when airlines loaded prices manually onto electronic systems, but pricing changes in real time these days. What matters is on what day you fly, not on what day you book. 

Google Flights recently reported on the cheapest time to book flights for Thanksgiving and Christmas holidays. While flights really are cheapest on Tuesdays, according to historical data, they have only been 1.3% cheaper than tickets booked on Sundays — the most expensive day of the week for buying airfare. 

Some websites offer special rates or "secret" deals   

Online travel agencies (OTAs) like Expedia and its several competitors can sometimes find cheaper flights than you'll find directly from the airline, but you can see all of these rates via Google Flights. If an OTA has a lower price than the airline's own, it will be displayed in the search results. 

VPNs: When they're useful

While a VPN can't reliably help you book cheaper flights, having one can protect your digital privacy and security, especially when you travel. VPNs allow you to get online through a private, secure server connection that makes your internet activity far more difficult to trace. They can also allow you to stream shows from other countries and access international websites from anywhere in the world.

You can often find the best VPN deals on longer-term plans, typically by subscribing for a year or longer. Many companies also offer free trials so you can test out the service before you commit. 

How we checked flight prices with a VPN

We picked two popular routes in the United States at two popular travel times, using Google Flights to look up prices. 

We first searched flight prices via a regular connection to an Internet service provider in the US. Then we switched to a VPN, using five of the most popular services, and repeated the searches while appearing to be in a different country. 

The routes and times we picked were: 

• Chicago to Seattle, around the Thanksgiving holiday, departing Tuesday, November 26, and returning Saturday, November 30
• Nashville to New York City, for a long weekend just before Christmas, departing Thursday, December 12, and returning Monday, December 16

Here's what we found for each VPN provider.

ExpressVPN

Express VPN has proven its worth with its ease of use, clean interface, and straightforward installation on multiple devices. We've used it on the road, without a hitch, in dozens of different countries including China, where it bypassed the Great Firewall easily. 

Original flight price, Chicago to Seattle: $361

ExpressVPN price: $361 

Original flight price, Nashville to New York: $99

ExpressVPN price: $99 

The prices were the same, with or without VPN.

NordVPN

NordVPN stands out for the number of servers around the world it can use, and for its speed and reliability when streaming and gaming. 

But when it came to flight booking, using NordVPN yielded the exact same prices for our sample flights as using a regular connection: 

Original flight price, Chicago to Seattle: $361

NordVPN price: $361 

Original flight price, Nashville to New York: $99

NordVPN price: $99 

Surfshark

Surfshark can use more than 3,200 servers across 100 countries, and has a wider selection of servers based in Africa than most competitors.  

But when it came to finding low fares for our sample flights, using Surfshark did not produce different results from other VPNs: the prices were the exact same.

Original flight price, Chicago to Seattle: $361

Surfshark VPN price: $361 

Original flight price, Nashville to New York: $99

Surfshark VPN price: $99 

Cyberghost

Cyberghost offers 24/7 live chat support and an especially good list of servers optimized for streaming, at relatively low prices. 

But when it comes to airfare? You guessed it: on Cyberghost's VPN, we found identical prices to a U.S.-based connection.   

Original flight price, Chicago to Seattle: $361

Cyberghost VPN price: $361 

Original flight price, Nashville to New York: $99

Cyberghost VPN price: $99 

PIA VPN

Private Internet Access (PIA) is a VPN with servers in 90 countries and the ability to block ads, trackers, and malware.

Using it to look up our sample itineraries on Google Flights, though, found the same prices as searching from the US:

Original flight price, Chicago to Seattle: $361

PIA VPN price: $361 

Original flight price, Nashville to New York: $99

PIA VPN price: $99