Airlines are rushing to add preflight COVID testing. Here’s why it matters.

If you're planning to travel internationally, odds are that you're going to need to pack a negative COVID test.

As countries begin to reopen to tourists, they want to ensure that visitors aren't bringing the virus with them. That's why nearly every country currently open to U.S. citizens requires a recent negative test.

Over the past few weeks, preflight testing initiatives have stolen the limelight. As Hawaii geared up to say aloha to interstate travelers sans 14-day quarantine on Oct. 15, travelers seeking to avoid the two-week isolation period are now required to show a negative COVID result from no later than 72 hours before flight departure.

Getting a fast and reliable COVID test remains a challenge for many across the country. Airlines recognize that — and in many cases, accessing preflight testing is a major roadblock to getting would-be travelers in the skies.

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The solution? Offer passengers an easy and convenient preflight testing option. That way, flyers know that they have access to a reliable test and airlines can stimulate some demand.

Henry Harteveldt, president at Atmosphere Research Group, said it best in an interview with TPG: "it all boils down to one word — confidence. If people are confident that they can get tested, then they will be more confident to travel."

In the weeks leading up to Hawaii's reopening, United Airlines became the first U.S. carrier to offer preflight testing options for travelers from San Francisco headed to the 50th state. In partnership with GoHealth Urgent Care and Dignity Health, United opened an on-site rapid testing center that promises to deliver results in about 15 minutes. This means that flyers won't have to worry about making appointments or turnaround times at other clinics. (There's also a cheaper, at-home option as well.)

United partnered with Hawaii officials to ensure that if you test negative on one of these COVID tests, you won't need to quarantine upon arrival.

Having the peace of mind that you won't need to spend two weeks in your hotel room is likely enough to convince some flyers to book flights to Hawaii — and fly United, too. According to Harteveldt, "airlines offering this convenience are hoping they will get bookings and capture more of the market."

But, of course, UA's competitors responded quickly. Within a week, Alaska, American and Hawaiian all announced similar preflight testing initiatives. Though JetBlue doesn't fly to Hawaii, the carrier partnered with a Vault Health to offer a discounted at-home test to its flyers.

In this hyper-competitive industry, airlines rarely let a competitor have an advantage. The latest airline to get in on the action is Lufthansa, which is trialing "COVID free" flights that would require passengers to take a rapid test (and produce negative test results) before boarding.

Related: 5 things to know about testing and visiting a reopened Hawaii

In fact, Harteveldt compared the recent flurry of preflight testing news releases to the bevy of cleanliness programs announced back in March and April. "We saw at the beginning of the pandemic that airlines used hygiene and cleanliness as a marketing tool. Now, they will use rapid preflight testing as a marketing tool," he explained.

It's not just airlines that are making preflight testing readily available to passengers. Airports are jumping on the bandwagon too.

Over the past few months, we've seen select U.S. airports open preflight testing centers. Tampa was one of the first, but Hartford, Newark, New York-JFK and others joined the party more recently.

Oakland Airport also offers preflight testing. But OAK is unique in that testing for Hawaii travel won't have out-of-pocket costs. For now, United's on-site rapid offering at SFO costs $250 per test. Consider a family of four — even if flights from Oakland are slightly more expensive than from San Francisco, saving $1,000 could easily be worth the more expensive flight and drive across the bay.

As airlines and airports start competing on preflight testing, it's clear that this "optional customer convenience" is well on its way to becoming part of the new normal — and perhaps the future of travel.

Take a look at American Airlines' preflight testing program. When the Fort Worth-based carrier first announced it, the carrier went well beyond its U.S.-based competitors. In addition to offering it for Hawaii-bound passengers, American outlined plans to use in-airport testing as a way to open international markets.

At first, the carrier announced that it's partnering with Jamaica, the Bahamas and the greater CARICOM (Caribbean Community) countries to offer convenient preflight testing options. Just three days later, AA added Costa Rica to its growing list of destinations.

As more and more countries seek to safely reopen, expect to see more pre-travel testing partnerships. "It's a good way to help spur travel to international destinations," remarked Harteveldt.

Related: American becomes latest carrier to offer preflight COVID testing

These initiatives aren't just about reducing the barriers to leisure travel, though.

In a way, they're sowing the seeds for the future of business travel. Harteveldt reasoned that offering preflight testing is a "subtle message" to business travelers: "If you need to travel for business, you can come to the airport and get an on-site test." With the "autumn of discontent" just beginning, carriers are looking for anything to help stimulate business demand.

Either way, the airlines win by making it easier for customers to take to the skies. States and countries benefit from being able to safely reopen and bring in tourism dollars. Perhaps most importantly, customers enjoy a convenient testing option. Plus, as competition increases, hopefully the cost of testing decreases over time.

And perhaps one day, a rapid COVID test might even be included with your booking.