At a growing number of airports, passengers no longer have to fish their laptop or bag of travel-size liquids out of their carry-on luggage before sending it through the X-ray machine. Instead, both can stay packed thanks to a new generation of computed tomography (CT) scanners that are steadily replacing traditional checkpoint equipment across the country.
The upgrade is part of the Transportation Security Administration’s (TSA) yearslong effort to modernize airport security. After first testing CT scanners at a handful of airports in 2018, the agency has steadily expanded the technology across the country. As of July 6, TSA had installed 1,162 CT scanners at 296 airports, according to a TSA spokesperson, with plans to continue replacing its existing X-ray fleet as funding allows.
The scanners don’t just make life easier for travelers. They also improve security by creating high-resolution, three-dimensional images that TSA officers can rotate and inspect from multiple angles, reducing the need for hands-on bag checks.
But the technology comes with an unexpected trade-off.
The openings on the CT scanners are smaller than those of many of the older X-ray machines they’re replacing. But before you panic about your carry-on fitting through: This isn’t likely to affect most travelers. Even larger bags that push the upper end of airline carry-on size limits—such as the expanded version of the Away Bigger Carry-On Flex—should still fit through the scanner, which measures 24.5 inches wide by 16.5 inches tall. The issue is more likely to arise with bags that exceed typical carry-on dimensions or have unusually bulky wheels, handles, or overstuffed exterior pockets.
If that happens, TSA officers will either manually screen the bag or direct the traveler to another security lane without the CT scanners, according to the agency. Even though laptops and liquids can stay packed for those in the CT scanner lanes, TSA still requires all belongings—including carry-on bags, jackets, and other personal items—to be placed in a screening bin.
As the technology becomes more widespread, it’s also changing one of the biggest practical differences between the standard screening process and TSA PreCheck. One of the expedited screening program’s marquee perks has long been allowing members to keep their laptops and liquids packed, but as CT scanners become more common in regular screening lanes, travelers without PreCheck are increasingly getting the same convenience.
TSA, however, says PreCheck’s value extends well beyond the scanners.
“As CT scanners become more common in standard lanes, TSA PreCheck retains unique advantages such as expedited screening, shorter lines, and fewer requirements for removing shoes, belts, and light jackets—benefits not tied to CT scanner deployment,” a TSA spokesperson told Afar. However, it’s worth mentioning that in July 2025, TSA eliminated the long-standing requirement for most passengers to remove their shoes at security checkpoints, citing improved screening technology. That said, travelers can still be asked to remove them for additional screening or other security reasons (for instance if they contain enough metal to set off the detectors), but it’s no longer a standard requirement.
“TSA will continue to adapt PreCheck as technology and traveler expectations evolve, and CT scanners are also being installed in some PreCheck lanes at select airports,” the TSA spokesperson said.
For now, travelers should continue following instructions from TSA officers, since many airports still operate a mix of traditional X-ray machines and CT scanners. But as the new technology expands, travelers can expect a more consistent checkpoint experience—one where unpacking a carry-on is becoming less common.
