We Compare Three-Across Child Car SeatsKatherine Keeler - Car and Driver"Hearst Magazines and Yahoo may earn commission or revenue on some items through these links."We've been testing convertible car seats for years, and it's easy to understand why they're so popular. Who doesn't love a one-and-done purchase? The downside is that convertible car seats are usually bulky and often wider than their nonconvertible counterparts, which can make them difficult to fit in smaller vehicles or side by side, three across.So what do families with multiple children do when they need every child to fit in their car seats comfortably? They have to turn to slim child car seats. Even among slim seats, though, your options are limited when it comes to fitting three in a row.Chicco Fit3x ClearTex Ultra SlimKatherine KeelerChicco Fit3x ClearTex Ultra Slim$230 at chiccousa.comGraco SlimFit3 LX 3-in-1Katherine KeelerGraco SlimFit3 LX 3-in-1$249 at amazon.comThe Chicco Fit3x ClearTex Ultra Slim and the Graco SlimFit3 LX 3-in-1 are designed to fit three car seats side by side across a vehicle's bench seat. Both seats measure just 16.7 inches wide, making them two of the slimmest convertible car seats available (that's 2.1 inches narrower than our top pick from our last convertible-car-seat test, the UppaBaby Rove).More Child Car Seat Tests: Best Rotating Convertible Car Seats, Best Convertible Car Seats, Best Electric Ride on Cars for KidsHow They Stack UpChicco Fit3x ClearTex Ultra SlimRear facing: 5–40 pounds, up to 43 inchesForward facing: 26.5–65 pounds, 38–54 inchesHigh-back booster: 40–100 pounds, 44–57 inches; age 4 and olderMSRP: $229Graco SlimFit3 LXRear facing: 5–40 pounds; up to 49 inches, provided the child's head remains at least 1 inch below the top of the headrestForward facing: 26.5–65 pounds, up to 49 inchesHigh-back booster: 40–100 pounds, 43–57 inches; age 4 and olderMSRP: $299What They Have in CommonIdentical 16.7-inch external widthIdentical interior shoulder roomIdentical 13-inch seat depthNearly identical top-harness-slot heightsRear-facing LATCH installation up to 40 poundsTen-year expiration periodFAA approval for use on airplanesHow They DifferPriceThe Chicco Fit3x costs $229, while the Graco SlimFit3 LX is priced at $299.LatchesThe Chicco has modified hook-style connectors called Mini-Grip connectors, while the Graco has push-on LATCH connectors.AdvertisementAdvertisementA push-style LATCH purist, I like the familiar seat-belt-like click that confirms the connector is engaged. But Chicco's Mini-Grip LATCH releases work exceptionally well, and during this round of testing, I found them easier to use.Built-In Lock-OffsThe Chicco has two cinching built-in lock-offs, one for rear-facing installation and one for forward-facing installation. The Graco has a latch style lock-off in the forward-facing belt path but not the rear-facing belt path.Reclining PositionsThe Chicco offers six recline positions: three for rear-facing use and three for forward-facing use. The Graco has four total recline positions, two for each direction.Height Limits and Harness HeightsBoth seats have a rear-facing weight limit of 40 pounds, but their height limits differ. The Chicco allows rear-facing use up to 43 inches, while the Graco allows rear-facing use up to 49 inches as long as the child's head remains at least 1 inch below the top of the headrest.AdvertisementAdvertisementMost children will reach the 40-pound weight limit before reaching the Graco's maximum rear-facing height. Still, the Graco may be a better fit for a particularly tall, lightweight child.The Chicco has a listed forward-facing height limit of 54 inches, compared with 49 inches for the Graco. However, children typically outgrow a forward-facing harness when their shoulders rise above the highest harness position, rather than by standing height. Since the two seats have nearly identical top harness slots, the Chicco's higher listed standing-height limit may not translate into a meaningful advantage.The Chicco is on the left, and the Graco is on the right, with both headrests raised to their highest positions. Despite the difference in overall headrest height, the top harness positions are nearly identical.Katherine Keeler - Car and DriverThe CupholdersI may have spent more time thinking about these cupholders than was strictly necessary, but the two seats take such different approaches that I couldn't ignore them.The Chicco uses flexible cupholders that attach to plastic brackets on the sides of the seat. The problem is that those cupholders extend to the side, which creates an issue when two seats are installed next to each other. Once they're pressed up against an adjacent car seat, it becomes difficult to see how a child's cup would fit inside. Maybe I'm missing something, but the design is confusing for a three-across setup.See what I mean about the cupholders?Katherine Keeler - Car and DriverThe Graco's cupholders are a much more practical solution. They attach to the front of the seat rather than extending from the sides, so they don't get squashed when against another seat. They're also removable with the push of a button.MaterialsThe Chicco Fit3x ClearTex uses fabrics and foams that inherently meet anti-flammability requirements, so it doesn't have to layer on chemicals, and comes in three different colors: Black, Lupine, and Oat. The Graco SlimFit3 LX uses covers treated with flame-retardant chemicals and comes in two different colors: Katrina and Kunningham. The Graco also has mesh jersey fabric on the sides for increased breathability.The Verdict?After comparing the two, the Chicco Fit3x is the seat I'd recommend. It costs $70 less than the Graco, offers more recline positions, includes a rear-facing lock-off, and avoids flame-retardant chemicals. The Chicco's flexible side cupholders are questionable in a three-across setup—but who needs easy access to a drink when Mom and Dad are there to pander to your every need while also carting you around town?AdvertisementAdvertisementThe Graco SlimFit3 LX does offer a few advantages that may appeal to certain parents and car owners. Its more upright rear-facing position takes up slightly less room front to back, and its front-mounted cupholders are far more practical when the seat is installed next to another car seat. It also offers a more generous listed rear-facing height limit, which could benefit particularly tall, lightweight children.Why Trust Us?Katherine Keeler - Car and DriverThe Gear Team helps readers make informed purchasing choices about automotive gear, tools, and accessories through hands-on product evaluations and comprehensive testing. Car and Driver's renowned testing standards mandate that we use all products we feature and that our findings and recommendations are based on personal experience and knowledge—not hype. We won't claim to have tested something we haven't, and we'll never recommend a product we wouldn't buy ourselves.The Gear Team's product selection and gear picks are editorially independent; Car and Driver has a strict policy against accepting payment for placement in articles.We've evaluated dozens of product categories, including tonneau covers, dash cams, and car sun shades. Visit our Tested & Trusted collection to see the very best in automotive gear. Read more about our testing process here.AdvertisementAdvertisementYou Might Also LikeGift Guide: Best Ride-On Electric Cars for KidsFuture Cars Worth Waiting For: 2025–2029