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Road tripping means you can bring pretty much anything — and you often do. Soon your trunk is full before you realize it. Then the back seat gets taken up, followed by the space at your feet. Next thing you know, you can’t even see out the rear-view mirror. That’s why a roof cargo box is a must-have for any sort of vehicular travel. Not only can it match your trunk’s storage capacity, but it's a secure place to stash dirty gear as well as snow-covered skis, snowboards, boots, and helmets.
But before you get a cargo box In almost all instances you’re going to need a roof rack system. These systems typically consist of two cross bars that bridge the width of your roof and can hold your box as well as other sport-specific carriers for bikes, skis, stand-up paddle boards, kayaks, and canoes — even a luxe rooftop camping tent. Depending on your vehicle, you may also need towers to attach the bars to your car and elevate them off your roof; get the same brand for both the cross bars and towers to assure compatibility. The variations on bar kits are staggering, but most major manufacturers have tools that help you narrow your options based on your car’s make, model, and year. The only time you don’t need bars? When you opt for a less-expensive cargo bag, which can sometimes be secured to factory mounts or rails found on some SUVs, trucks, and sedans.
Once you’ve got your bars and towers sorted, the biggest factor in selecting the best cargo box is its size and its shape. You want space ample enough to handle whatever you’re going to toss inside, of course. But those looking to haul a quiver of skis for the entire family or a few surfboards will want a box long enough to accommodate your hard goods, while others who just want some extra space for a variety of items can consider wider, shorter models. Those with hatch-backs that open vertically should also be sure that the cargo box won’t interfere with the door, and those who want their cargo box to look like part of their luxury vehicle should consider boxes that are made with higher-quality materials or that are low-profile, which provides a sleeker silhouette that looks better, creates less drag, and less noise than bulkier models.
If you need a little advice when it comes to picking one out, keep reading to find the best rooftop cargo boxes to buy today.
Our Top Picks
Best Overall: Yakima Skybox Carbonite
The Skybox Carbonite is a long carbo box that can handle camping gear for up to four travelers, as well as skis and snowboards up to 215 centimeters long. Designed with internal lid stiffeners, it’s both durable and easy to open and close from either side, with a tapered design to reduce hinge interface and increase internal space for awkwardly-shaped gear. SKS locks come included, and the Superlatch tech ensures that the lid will lock securely to the base to protect your gear.
The sleek, aerodynamic design cuts down on drag and wind noise, and the quick-release hardware makes it easy to mount; it works with most round, square, and aerodynamic bars, with a minimum/maximum cross bar spread between 24 to 42 inches. As with most Yakima boxes, it’s made in the United States with up to 80 percent recycled material, and you can add a cargo net (separate purchase) that attaches to built-in tie-down points and divides the storage space into four-foot squares. The Skybox comes in five sizes, from 12 cubic feet up to a cavernous 21 cubic feet.
Best Value: Thule Outbound
Less a full-on cargo box and more a super-durable cargo bag, the Thule Outbound delivers 13 cubic feet of storage in a package that weighs only 3.5 pounds. It easily attaches to a car’s factory-issued racks or raised rails, removing the costly expense of buying a bar kit.
The Outbound ties to your vehicle with heavy-duty, double-stitched webbing straps, while twin compression straps help secure the load to cause minimal friction and noise while driving. Made of double-coated IP-X2, phthalate-free TPE laminate material that’s been certified to be weather resistant, it’ll provide amply protection from all the elements. A three-sided zipper makes it easy to access, and a storm flap that covers the zipper seams reinforce weather protection.
Locks aren’t included — but they’re not needed, as bags aren’t as secure as hard plastic boxes, but you can easily remove the Outbound and stash it in your trunk or garage until you need it.
Best for Longer Gear: Inno Shadow 16 Cargo Box
If your road trips always include skis, snowboards, surfboards, deep sea fishing poles, or other items that often stretch the length of most sedans, the Inno Shadow 16 has you covered. Though it only boasts 11 cubic feet of storage, it can accommodate up to six snowboards, eight skis, or two surfboards. The proprietary Memory Mount System makes it easy to toss the box on and off as needed without fiddling with over-engineered mounting hassles. Its svelte profile and “Diffuser Design” lets it slice through wind to reduce drag and noise, with a three-layer sheet base construction that makes it lighter and stronger than most conventional carbo boxes. As with most models, it opens from both sides and has universal cross bar compatibility.
Best for Big Loads: Thule Motion XT XXL
With a voluminous 22 cubic feet of storage, the Motion XT XXL is Thule’s highest-end box and comes with loads of bells and whistles, including an internal ski carrier, a slide-lock security system, as well as a total load capacity of 165 pounds. The extra-wide PowerClick quick-mounting system (which offers a welcoming “click” sound as you twist the mounting dial to confirm that the box is properly connected) makes for a fast and secure fitting, and it’s built to sit a bit forward on your crossbars to provide full trunk access for hatchbacks.
Grip-friendly outer handles and supporting lid-lifters make it easy to open from either side of the vehicle even when wearing gloves, with a clever slide-lock system with separate locking and opening functions to let you know when the lid’s in place and closed securely. It marries nicely with most after-market bar kits and comes in black, gray, and white.
Best Design: Yakima Showcase
The Showcase is constructed of high-quality, durable plastic, and the exterior comes with a high-gloss automotive-quality finish to deliver a decidedly more modern look. But the Showcase doesn’t just get by on appearances. The box opens from both sides, with a tapered tail to provide excellent tailgate clearance. The made-in-the-U.S. box comes with SKS locks, an intuitive push-button latch to securely close the lid and internal lid stiffeners that bolster the box’s overall strength and makes easy to open and close the lid.
Available in both black and silver, it comes with an option for 15 or 20 cubic feet of storage and works with most square, round, and tapered cross bars.
Best for Streamlined Storage: Whispbar Aero Compact Cargo Carrier
Whispbar made a name for itself by introducing some of the industry’s most aerodynamic and sleek cross bars before moving onto sport-specific mounts for things such as bikes and kayaks. This attention to design-forward aerodynamics continues with their Aero Compact Cargo Carrier. Available in either black or silver high-gloss finish, this box has been intentionally designed for smaller, more compact vehicles, proffering 10.8 cubic feet of storage that can accommodate skis up to 155 centimeters in length.
The lid has dual-layer construction, which adds stiffness for durability and ease-of-use while reducing drag for better MPG, as well as to lessen the noise. Spring-loaded hinges make accessing the box from either side of the vehicle a breeze, with lockable Smartlatch handles help make sure everything is shut up tight. Clamp mounts make the box compatible with most roof rack bar systems, though you’ll probably want to upgrade to one of Whispbar’s mounts to complete the look.
Best for Space: SportRack XL Cargo Box
No, the XL Cargo Box won’t win any design awards. Its two-tone aesthetic is as utilitarian as its name, but with 18 cubic feet of space, you get a lot of storage at a price that won’t break the bank. Unlike other boxes in this article, it opens only on the passenger side, keeping you safe from traffic when handling the insides. The high-density plastic is a tough as it looks, and it fits most factory and after-market cross bars rated to carry up to 150 pounds.
The U-bolt mounting kit takes some fiddling, and the XL Cargo Box requires some additional assembly to get it up and running. Locks come standard to help secure the contents from prying hands when you’re not hitting the pavement.
For Smaller Loads: Yakima Rocketbox Pro
With a length of 58 inches, the Rocketbox Pro won’t accommodate skis or snowboard — and for the non-skier/snowboarder, that’s perfectly fine. Instead, you get storage that ranges from 11 to 12 to 14 cubic feet, with push-button access for secure lid closure and easy access from either side of your vehicle.
The wide design makes it considerably more aerodynamic and assures you’ll be able to open your hatchback easily. No assembly is required for the box, and easy, tool-free installation (and removal) from most cross bar kits make it easy to toss the 30-pound box off when not needed.
SKS locks come included, and the matte-black textured finish adds a touch of class to the whole affair. The 12-cubic-foot edition provides enough storage for hauling gear for two campers, ideal for compact SUVs and smaller cars.