A man loads gear into his rooftop cargo carrier on a car that is parked by a glass building.
A close-up of a person loading their skis into a Thule ski box.

Cargo box fit guide: Find the best rooftop cargo carrier


Find the best rooftop cargo carrier for your vehicle and lifestyle with this Thule cargo box fit guide!


Cargo boxes are a great way to increase the packing capacity of your car. Whether you’re hitting the slopes, going on a family vacation, or just need more space, a cargo box is a super versatile solution.


But with all the different types of cargo boxes and cargo box sizes, how do you know it will fit your car? And how can you make sure it will fit all the things you want to pack?


This Thule cargo box fit guide aims to clear some of this up. We’ll show you how to make sure the cargo box fits your car and how much you can pack inside the different cargo box sizes.


In this article we’ll go through:

A close-up of a woman grabbing her skis from an open roof box with Thule duffels inside.

Some recommended ski cargo boxes:

Some recommended roof boxes:

Some recommended roof boxes:


A flatlay of the Thule Vector L roof box featuring all the ski gear you can fit inside.
A flatlay of the Thule Motion XT XL roof-box-featuring all the ski gear you can fit inside.

Comparing our boxes: Thule Force XT vs Thule Motion XT vs Thule Vector

Thule Force XT, Thule Motion XT and Thule Vector are three state-of-the-art roof boxes that are designed for increased aerodynamics and enhanced user-friendliness. So, what exactly are the differences?

What they all have in common:

  • All three boxes have dual-side opening meaning that you can easily open the box from either side of the car.
  • They are designed to be as aerodynamic as possible.
  • They’re all constructed with hardy ABS plastic which is impact resistant.
  • They also use PowerClick mounting hardware, so that you always know you’ve mounted the box to your roof racks correctly.
A car drives in a snowy forest with a Thule Motion XT rooftop cargo carrier.

Thule Vector

These cargo boxes are the most premium of the lot. They have all the features of the Thule Motion, plus more for even smoother usability.

The felt lined interior gives your gear extra protection, and the white lid and LED light helps you see your packing in the dark.

The reinforced lid on the Thule Vector is the strongest and gives the box extra protection from impact (although all Thule cargo boxes are built to withstand lots of force).

A car with a Thule Vector rooftop cargo carrier is parked in a snowy forest.

Thule Motion XT

These boxes can go up to XXL sizes, the largest Thule cargo box size. It has a handlebar which makes the box easier to open.

It also has the SlideLock system, a super handy feature which makes closing your box super simple. It means that the box automatically shuts when closed, so that you can close it with just one hand. The lock indicates when the box has been shut correctly with a red indication button.

A car drives in a snowy forest with a Thule Motion XT rooftop cargo carrier.

Thule Force XT

Thule Force XT is a versatile cargo box you can rely on to carry all kinds of cargo.

It’s easy to mount on your roof racks and clicks when it’s properly mounted so that you know you’ve secured it correctly.

It can also be opened on either side (which you’ll be thankful for when you park on different sides of the street).


A close-up of a car with a hatch that is open even with a Thule rooftop cargo carrier on the roof.
An illustration that shows what parts of the car roof to measure to determine hatch clearance.
An illustration showing how you can pack your Thule rooftop cargo carrier.

A car has a Thule Arcos towbar cargo carrier and a man gets out of the car and a family walks towards him.

Rear-of-car solutions

Rear-of-car cargo solutions are great for those who don’t want anything on the roof of their car. With a rear cargo box you can optimize the range of your vehicle and turn your compact city car into an adventure car!

You don’t have to buy a big vehicle to transport your family and gear. Our rear cargo boxes turn your compact car into the perfect family car where you can store the gear you need for everyday errands, a day at the golf course, or a trip to your summer house.

The rear of a car with Thule Arcos towbar cargo box, where it is completely integrated.
Bring all your gear without compromising on the range of your electric or fuel-driven car
A vehicle drives down the road with a towbar cargo carrier mounted to the back.
Works for vehicles and EVs that don’t let you load anything on the roof
A vehicle is parked in a field with a towbar cargo box and a rooftop tent.
A versatile solution that turns a small car into an adventure car
A white SUV drived with a bike and kayak on the roof, a towbar cargo box on the trunk.
Easy to pack and saves space on the roof for more gear

Optimizes the range of your vehicle

Rear-of-car solutions take you and your gear farther...

Rear cargo boxes have no impact on your battery or fuel consumption*. Thanks to the rear cargo box’s location at the back of the car, it’s a spot that naturally causes very little wind drag. With a rear cargo carrier, you can pack your vehicle full of gear without majorly impacting the range of your electric vehicle or fuel-driven car. This will help you save on fuel or electricity costs.

A sketch of the Thule Onto rear cargo carrier and the aerodynamic design.

For electric vehicles that can’t handle a heavy roof load

Certain electric vehicles have restrictions on roof load capacity. With a rear-of-car cargo carrier solution, you don’t have to worry about this. Simply attach your bike rack or cargo carrier to your hitch and get ready for the adventure.
𠊊 car has a Thule Arcos hitch cargo carrier and a man gets out of the car and a family walks towards him.

Bring more, go farther

When we say that rear-of-car solutions take you farther, we really mean farther. Both internal testing at the Thule Test Center and testing by external sources have shown that a hitch cargo carrier leads to less fuel or electricity consumption than having nothing on the car at all.

A woman loads items into the trunk of a car while her children help load items into the rear towbar box.

Get better range with a rear-of-car cargo box

We know from data models and wind tunnel tests at the Thule Test Center that a rear-of-car cargo solution makes for better aerodynamics than having nothing on your vehicle at all.

It may seem strange at first – how can you possibly lower the air resistance by adding a large cargo box to the back of the car? But the results speak for themselves.

We drove a total of 5400 km in varying weather conditions with a fleet of Volkswagen ID4 – one of the most popular electric vehicles on the market. The results were interesting, to say the least.

The average consumption (kWh/100km) of a vehicle with the Thule Arcos hitch cargo carrier was 95 %. This means that when we drove the Volkswagen ID4 with Thule Arcos mounted, the range improved by 5%* compared to the cars with nothing on them at all. So based on the battery of size of the ID4 and the consumption measured during the tests, we could travel roughly 17 km further*. This data is also backed up by computer simulations that showed a similar result.

We were able to drive farther – and at the same time, we could bring more gear.

A vehicle drives down the road with a towbar cargo carrier mounted to the back.

Tested in real life

This is supported by an external test by Vi Bilägare, Sweden's largest car magazine. It was founded in 1930 and features travel reports and test drives of cars and car accessories. They tested a roof box and our Thule Onto rear cargo box with both electric and fuel-driven cars.

Vi Bilägare found that the towbar cargo carrier created less wind drag than a roof box, and consumed less fuel and electricity than a car with nothing on it at all.

“One way to get more packing space without increasing energy consumption is the latest trend of mounting a cargo box on the car's towbar,” they explain in their article, “We found that both the petrol car and the electric car had slightly lower consumption with the box fitted than when the car was running completely empty on the test route”.

Read the article from Vi Bilägare (in Swedish).


A versatile solution

Rear cargo carriers are a versatile solution that gives you a range of creative ways to maximize the packing capacity of your vehicle.
A vehicle is parked in a field with a towbar cargo box and a rooftop tent.

Turn your compact city car into an adventure car

A rear cargo carrier lets you use your compact city car in a variety of ways. Load on your bikes and head out into the unknown one day, and pack your bags for a weekend trip the next. The choice is yours, we provide you with the solutions.

By the ocean, a white SUV drived has a bike and kayak on the roof, a towbar cargo box on the trunk.

Saves space on the roof

A rear-of-car solution saves space on the roof of your vehicle for other sports carriers. Why not put your luggage in the back, and your bikes or board on the roof?
A woman loads items into the trunk of a car while her children help load items into the rear towbar box.

Easy to pack your gear

Certain rear cargo carriers are tiltable, others sit very low down – but both kinds let you easily access the trunk of your car at any time. A rear cargo carrier is also easier to load or unload, since it’s closer to the ground.

Our rear-of-car solutions


Recommended rear cargo boxes

Thule Arcos is the most aerodynamic option and is perfect to use in the city with your compact electric vehicle. The hard-shell exterior makes it robust and stable, and the low-profile, curved design means you can access your trunk at any time. This sleek, modern rear cargo box is a natural extension of your car.

Thule Transporter Combi is a hard-shell cargo box with a tilt-down design for partial access to the trunk even with gear loaded. It's perfect for everyday errands or adventures off in the outdoors.

*Internal tests at Thule show that our rear cargo boxes have an improved effect on the range of your vehicle. However, many parameters can affect your vehicle’s fuel consumption or battery range. Therefore, you may see results that differ from ours.
*Internal tests at Thule show that our rear cargo boxes have an improved effect on the range of your vehicle. However, many parameters can affect your vehicle’s fuel consumption or battery range. Therefore, you may see results that differ from ours.

In the sunset, a family parked by the water with a car that has a Thule Arcos cargo box.

Pros and cons – why choose a hitch cargo carrier?

Why choose a hitch cargo carrier? Here are some hitch cargo carrier pros and cons so that you can choose the best cargo carrier solution for you.

Hitch cargo carriers are a great way to bring all the gear you need for fun outdoor adventures, they’re also a smart way to add more storage space to a compact city car.

Hitch cargo carriers are a great way to bring all the gear you need for fun outdoor adventures, they’re also a smart way to add more storage space to a compact city car.

But what exactly is the difference between a roof box and a hitch cargo carrier, and which one will fit your lifestyle the best?

In this guide we’ll dig into the pros and cons of hitch cargo carriers, and compare them to traditional rooftop cargo carriers.


A world of possibilities at the back of your car

Rear-of-car solutions take you and your gear further...

A sketch of a vehicle with the Thule Onto towbar cargo carrier in the back of the car.
Rear cargo boxes are the most aerodynamic solution thanks to their position at the back of the car.

...get more out of your vehicle...

...utilize your electric vehicle in ways you didn’t know were possible

A vehicle is parked next to a dirt road with a towbar cargo box mounted on the back.
Certain electric vehicles have restrictions on roof load capacity. With a rear-of-car cargo carrier solution, you don’t have to worry about this. Simply attach your bike rack or cargo carrier to your hitch or trunk, and get ready for the adventure.

Unsure whether to choose a rear cargo box or a roof box?


A vehicle is parked in the snow next to a snowy forest with a Thule Vector roof box.
Roof boxes are designed to be as streamlined as possible to decrease wind resistance. Thule designs some of the most streamlined boxes on the market. Rooftop cargo carriers are also the best option to transport your skis or snowboards. Keep reading below to see more differences!

Hitch cargo carrier pros and cons

A vehicle with a Thule Combi hitch cargo carrier and an open rear door.

Pros of a hitch cargo carrier:

  • Super aerodynamic. Thanks to the hitch cargo box’s location at the back of the car, it’s naturally an aerodynamic spot that causes no impact on your fuel consumption or the range of your electric vehicle*
  • Less wind drag means you use less fuel and electricity while driving with your gear packed
  • The boxes’ aerodynamic nature also makes them super quiet when you’re driving
  • They give you the option to store gear even if your vehicle – like certain e-vehicles – doesn’t let you put anything on the roof
  • Great if you want to leave space on the roof racks for other sports carriers
  • The hitch cargo carrier is closer to the ground which makes it easy to pack heavy items. If you’re a parent in a rush, for example, you’ll appreciate being able to throw your stroller in the rear cargo box without having to do any high lifting
  • Certain hitch cargo carriers can be combined with a bike rack

Cons of a hitch cargo carrier:

  • You take up more space at the rear compared to a roof box, which might make it harder to parallel park.
  • Since hitch cargo carriers can’t carry skis – a roof box or a ski rack is a better option for a ski holiday

Hitch mounted cargo carrier vs roof box

Aerodynamics

A black vehicle is parked on the street with a black Thule Vector roof box.

Roof boxes are designed to be as streamlined as possible and Thule designs some of the most aerodynamic boxes on the market. They are a great option for vehicles that can carry something on the roof.

A vehicle with the Thule Arcos hitch caro carrier is parked in the woods by a lake.

Towbar cargo carriers, on the other hand, have the advantage of being at the back of the car in a place that barely affects wind resistance at all.

Hitch trailer cargo carriers like the Thule Arcos generate little to no wind drag. This means that, with a Thule Arcos towbar cargo carrier, you’ll be using the same amount of gas or electricity as a vehicle without anything on it.

They’re a great option for those who do not want to carry anything on their roof.

Position on vehicle

Hitch cargo carriers are installed at the back of your vehicle. This makes them ideal for e-vehicles or other cars that cannot handle a heavy load on the roof.

Roof boxes, on the other hand, are positioned on the roof (pretty obvious considering their name!) and this can be handy, too. All roof boxes let you use the trunk as normal, and Thule roof boxes are specifically designed to not interfere with the trunk door.

If you want access to the trunk with a hitch cargo carrier you have to specifically choose a box that swings away, tilts down, or sits low enough so that you still have access to the trunk. Thule Arcos has a curved design that gives you space to put items in your trunk whenever you need to.

An advantage with the positioning of the trailer hitch cargo carrier is that it’s lower down to the ground. This makes it really easy to pack all your stuff, since you don’t have to strain or stretch to reach your box.


When carrying bikes or skis

Carry bikes at the back of your vehicle

If you want to carry bikes at the back of your vehicle, hitch bike racks let you do just that.

If you want to carry bikes at the back of your vehicle, hitch bike racks let you do just that.

Carry skis on the roof of your car

Roof boxes are a great option for transporting your skis. Especially the alpine-sized Thule roof cargo boxes, which are specifically designed for long skis up to 200cm. The largest Thule roof boxes fit skis up to 215cm. To find the right size for your skis, check out our guide on roof box sizes.

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