How to make sure the cargo box fits your car or SUV

Interested in buying a cargo box but unsure whether you’ll still be able to smoothly open the trunk of your car? Here are some tips when trying to work out which size roof box will best fit your car.

A black vehicle with a black roof box as the hatch open completely with a white background.

Hatch Clearance:

Hatch clearance means that your trunk can be opened completely without interfering with the roof box. Thule roof boxes are designed specifically so that you can open your hatch without a problem.

Unsure if you’ll be able to open your car’s rear door with your new box?

This is how you can calculate the hatch clearance:

1. Hatch Clearance:

Open your trunk door completely.
Measure from the center of your vehicle's front roof rack to the point where the roof meets the hatch.
Compare this number to the "Front Clearance" dimensions that are specified in the roof box’s user manual. If your vehicle measures greater than the number listed, that cargo box will fit your vehicle without contacting your hatch.

2. Bar spread:

Also, have a look at the maximum bar spread. This is the distance between your roof racks. If your bar spread is the right size according to the roof box’s user manual, then you’ll have full access to the trunk.

Some roof racks can be moved further forward on your vehicle. If possible, this might also help allow for hatch clearance.

An illustration that shows what parts of the car roof to measure to determine hatch clearance.

How much can you pack in your roof box?

That depends on the maximum roof load of your car or your roof box.

Thule roof boxes have a load capacity of about 75kg/165lbs and most vehicles have the same maximum capacity. Double check with your car manufacturer to see if that’s the case for your car.

In general, when packing your roof box, try to pack lighter, bulkier items like tents, clothes or sleeping bags.

An illustration showing how you can pack your Thule rooftop cargo carrier.

For the smoothest possible ride, try to pack your cargo box with the proper weight distribution.

Half of your gear should go in the space between the roof racks. The second half should be organized at either end of the roof box.

Does the roof box work with my roof racks?

Almost all Thule roof boxes work together with our Thule roof racks, although some will require an additional adapter. To see if the roof box fits your roof racks, head to the rooftop cargo carrier listing page and click “Fit - Select roof rack” to see if the roof box fits your Thule roof rack.