Should you panic when you see “SSSS” printed on your boarding pass? Social media users are going viral for sharing their experiences after spotting the four letters upon arrival at the airport.

So what does SSSS mean if it shows up at check-in?

“SSSS are indeed four dreaded letters that no traveler should see their boarding pass” Zach Griff, senior aviation writer for New York travel blog The Point Guys, told Fox News Digital.

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“This stands for ‘secondary security screening’ and is a measure implemented by US security authorities to screen certain passengers with additional checks.”

Jordyn Verrzera and JT Mocarsk went viral on TikTok for sharing their unfortunate experiences after finding “SSSS” on their boarding pass. (The Mobile Homie)

The Transportation Security Administration (TSA) will screen passengers prior to official flight departure.

“Selectees for this enhanced security are chosen in the days leading up to a flight when airlines share the manifest with US security authorities,” Griff added.

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Griff said most people who receive SSSS before their flight won’t be able to check in online and will receive a printed ticket from an agent — which is exactly what happened to Jordyn Verzera and JT Mocarski, creators of the travel blog “The Mobile “. Homie.””

“SSSS” stands for “security screening secondary selection”, which means that the recipient will have to go through some additional security measures on their journey. (The Mobile Homie)

Creating travel content duo from Arizona shared their experiences on TikTok every time they noticed the four S’s on their boarding pass.

Whenever they get SSSS on their boarding passes and post it on social media, users flood them with questions in the comments section.

Verzera and Mocarski told Fox News Digital about what this additional screening process entails.

The first time Verzera and Mocarski met the four letters, only one of them was able to check in before their flight.

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Verzera tried to get her boarding pass on the airline’s app, but a notification appeared saying she had to check in with a gate agent, she said.

The waiting process and additional security measures you have to go through with SSSS can take hours. (iStock)

Verzera said she was confused until she spoke to an agent.

“They had to give me one printed boarding pass. He (Mocarski) could still use the digital one, and then I had to carry this pass. It was marked and circled and I had to show it every step of the way,” Verzera said.

“Instead of going through one form of security… you had to get to the gate earlier and they did a very thorough screening when you left. But the most important thing is that once we arrived, we ended up having to go through customs… and that’s when the really deep search began.”

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Verzera said every item she packed had to be removed from the bag, including toiletries. These items were then placed on a conveyor belt where everything was buffered. Her laptop also had to be turned on to get through security.

Verzera filmed a video showing a crowded line in front of her as she waited for three hours to get her boarding pass after receiving “SSSS” markings on her original ticket. (The Mobile Homie)

“It was a little intimidating the first time,” she said.

Verzera had to get to the airport early to get his boarding pass and had to stand in line for three hours. She said it took her another hour to get through the extra customs check.

In April, when Mocarski had gone through the SSSS process in Rome, it was significantly faster, he said.

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“It depends on the country … or where you go, like the severity of the search, what that entails,” Mocarski told Fox News Digital.

“SSSS can also be completely random and there is no way to know when you book your flight if you will be selected as SSSS.”

— Zach Griff, senior aviation writer for New York travel blog The Point Guys

Griff agreed with Mocarski’s point, adding that it depends on the airport you’re at, some requiring an early arrival and a “full refund.” Some airports may require a “custom interview along with multiple screenings.”

Mocarski believes social media may have slightly undermined the extra security measure, he said.

“At the end of the day, it’s random, like TSA agents, it’s not like they’re picking you. They know the lengths they have to go through to make sure they get through the check,” Mocarski said. .

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“It’s just staying calm and just respecting their time. And they’ll come back with you.”

“At the end of the day … they’re just doing your job,” he added. “I’m not there maliciously.”

Mocarski got his first “SSSS” marked on his boarding pass in April and added just an extra hour to his travel day, he said. (The Mobile Homie)

Griff said you could get SSSS for a variety of different reasons: “suspicious travel patterns, such as frequent one-way international travel or many visits to high-risk countries,” he said.

“SSSS can also be entirely random, and there’s no way to know when you book your flight if you’ll be selected as SSSS,” added Griff.

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Some people who received “SSSS” on a boarding pass have tried to apply for a compensation number with the Department of Homeland Security in an effort to never see the letters again, according to several travel blogs. (Chip Somodevilla/Getty Images)

Verzera said people may be concerned about “SSSS” because they feel the extra screening will cause them to miss their flight.

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She and Mocarski recommend getting travel insurance for this purpose.

They also said that when “SSSS” appeared on their boarding pass, the plane “waited” and did not leave any “SSSS passengers” behind.

Social media users are going viral for sharing their experiences with the dreaded “SSSS” that can appear on a boarding pass, meaning they’ve been shortlisted to go through initial security. (The Mobile Homie)

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“I think for us, and something we like to remind our friends about, is that the journey is not perfect,” Verzera said.

“You grow the most when you’re uncomfortable with travel — you just understand that it happens. Just stick with it and let it be a part of your day…get through it and then (say) ‘I hope it never happens again.’

Fox News Digital has reached out to the TSA for comment.