Trailer brakes are like snow tires. You don’t need them until you really need them. It doesn’t snow much in Missouri, so maybe they don’t know about trailer brakes down there, either. I was in the state recently at an event, and as I walked through a parking lot of unloaded trailers, I noticed that not one was equipped with brakes. When I asked about this, a local told me that there is no law in Missouri that requires brakes on a trailer. A quick scan on the Google revealed that he was correct, and also that Kansas and Kentucky also don’t require brakes for even a heavy boat trailer.

Disc brakes like this one are the best choice for boats launched in salt water. (Photo courtesy )

“There are 35 states that require brakes on trailers with a GVWR of more than 3,000 pounds, and have a pretty uniform law,” says Gary Potter, vice president at EZ Loader Custom Boat Trailers in Midway, Ark. GVWR (Gross Vehicle Weight Rating) refers to the total combined weight of the boat with gear and fuel, and the trailer. “The other 15 states are all over the board, some down to 1,000 pounds, but Texas is 4,500 pounds, which is crazy when you look at the physics. In an emergency, a half-ton pick-up truck cannot stop a 4,000-pound trailer safely.”

New Jersey and North Dakota seem to require brakes on any trailer used on the highway. New Hampshire requires any vehicle combination to stop in 30 feet at 20 mph. This checker board of trailer brake laws can get you in trouble if you travel far from home.

“You might be legal towing 4,000 pounds with no trailer brakes in Texas,” says Potter, “but cross into Arkansas it’s 3,000 pounds, and you must comply with the law of the state in which you are driving, not the law of the state in which you live.”

To see a great graphic of trailer laws, go to this page on the Brake Buddy website. However, it’s best to check directly with the state government to verify towing regulations, as I found some info online that seemed out of date. It also appears that some states have different regulations for campers, horse trailers, and boat trailers.

Depending on where you live, all boat trailers may be required to have brakes, or brakes may be at the discretion of the owner.

And before you think you are good to go without brakes because your trailer is under the legal limit, take a gander at the owner’s manual of your tow vehicle, which will list the maximum towing weight and may specify that trailers over a certain weight require brakes. Ignore that specification, and you could imperil your warranty or find yourself in a serious liability situation if you are in an accident, regardless of state law.

Potter believes that every trailer should have brakes, and I see his point. Even a light trailer can start pushing a tow vehicle around when traction is limited on rain-slick roads. And if you go anywhere near the mountains, I think brakes are a must.

“The issue of brakes is usually price-driven,” says Potter, who estimates that brakes add $500 to $800 to the retail price of a trailer, depending on the brake style. Not an insignificant amount of money, but think about it this way – how much body work or medical attention could you buy for $800? Put in that perspective, I think trailer brakes are a bargain.

The hot set-up for a boat trailer is disc brakes, especially if you are launching in salt water, which can cause corrosion problems with drum brakes unless they are rinsed out—which entails connecting a hose to a fitting on the back of the brakes. With disc brakes, you can just aim a hose behind the wheels. Disc brakes are also easier to service, and offer better braking performance than drum brakes, according to Potter.

Potter offers another important brake-safety tip: Always adjust your hitch height so that the trailer is level with the ground (trailer tongue horizontal). If the hitch is too high the trailer will push the rear of the tow vehicle up under heavy braking, compromising the braking effect at the rear wheels of the tow vehicle. If the hitch is low, the trailer pushes down on the rear of the vehicle, and lifts the front suspension, which will compromise both braking and steering control.

Written by: Charles Plueddeman
Charles Plueddeman is's outboard, trailer, and PWC expert. He is a former editor at Boating Magazine and contributor to many national publications since 1986.