If you own a trailer, the first accessory you want to invest in is a quality hitch or trailer lock. Unfortunately, trailers are often sought out by thieves since they’re relatively straightforward to steal and easy to sell once stolen. In addition, stolen trailers have a low rate of being recovered. Even if they are found, there’s a good chance all the stuff stored inside is gone. A trailer lock is a small investment that could potentially save you a lot of headache and heartache down the road. After all, the money spent on a trailer lock will be less than the cost to replace a whole trailer.

There are several different types of hitch and trailer locks available and in this article, we’ll take a look at the most popular, bestselling and cost-efficient products. We’ll also go into detail about why you need a trailer lock, what to look for when shopping for one, and how to choose the right one for your needs.

For more information on hitch and trailer locks, refer to our table of contents.

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1. Editor's Pick: Master Lock Receiver Lock (2866DATSC)

master lock swivel head receiver lock

Designed for vehicles, trailers, and RV hitch locks, this Master Lock receiver lock fits 1/2-inch and 5/8-inch receivers. The 1/2-inch pin is rated for Class I/II 3,500-pound load, while the 5/8-inch pin is good for Class III/IV 10,000-pound load. The usable length of the receiver pin is 2.75 inches.

The receiver lock features a convenient push-to-lock mechanism, so you simply have to push the lock body onto the pin and remove the key. It has a durable design with a weather tough seal and watertight cap which helps provide protection from moisture and dirt. The four-pin cylinder prevents lock picking, while the keyway is constructed with brass to make it resistant against corrosion.

There is also a patented, stainless steel swivel head that rotates 360 degrees for easy access. This is a padlock-style hitch lock that is used in place of the standard pin and clip to prevent theft.

2. Trimax Premium Key Receiver Lock (T-3BLACK)

trimax t-3black premium key receiver lock

Manufactured from high quality, forged hardened steel is Trimax’s premium key receiver lock. This product features a rugged black epoxy powdercoat and comes with an o-ring seal and watertight cap to help keep out dirt and corrosion. Trimax says the lock cannot “pop” open, nor can it be false locked. It’s easy-to-use with a 1/4 turn locking and unlocking the head.

The 5/8-inch pin fits all Class III, IV, and V receiver hitches and fits up to a 2.75-inch span. This is a type A key, which makes it a spring-loaded, seven-pin high security key. It is resistant to attempted drill outs and will not bend or break.

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3. Reese Towpower Universal Coupler Lock (72783)

reese towpower universal coupler lock

This premium lock comes from Reese Towpower and is a universal coupler lock measuring 9 inches by 9 inches by 3 inches. It’s manufactured with an aluminum body and heavy duty steel lock bar, designed to be a universal fit with a ratchet design with 11 locking positions. It can be used on 1 7/8-, 2-, and 2 5/16-inch couplers. The durable bright yellow finish acts as a theft-deterrent, while the premium lock resists picking, prying, and drill outs.

If you have never heard of the Reese brand, the company was originally founded in 1952 and has since become a household name in the heavy duty towing industry, as well as a market leader in automotive and recreational product solutions.

4. Cocoweb C-Lock Heavy Duty Locking Hitch Pin

cocoweb c-lock heavy duty locking hitch pin

Cocoweb’s C-Lock heavy duty hitch pin comes in 1/2- and 5/8-inch sizing. The 1/2- and 5/8-inch pins are available in silver, while the 5/8-inch pin features a black finish. This locking hitch pin has a standard design, featuring a weatherproof cap that protects the keyhole by keeping out water and grime as well as keeping the lock free of rust. No drilling or mounting is required to use this locking hitch pin, simply slide it in, lock it, and you’re ready to go.

The pin fits Class I, II, III, and IV hitches with a max outer width of 2.75 inches and comes with two unique laser cut keys. Cocoweb does caution to verify the dimensions of your hitch, as these locking pins do not fit all vehicle models.

The solid steel lock is a total of six-inches long and has a barbell locking mechanism designed to make the lock fit more snugly and securely.

5. Connor Trailer Hitch Lock

connor trailer hitch lock

Constructed from heavy duty solid steel with a durable black nickel finish is Connor Trailer’s hitch lock with a 5/8-inch pin for Class III, IV, and V hitches. This hitch pin fits most common hitch setups, including Class III/IV 2-inch by 2-inch receivers, and Class V 2.5-inch by 2.5-inch receivers. It has 3.5 inches of usable length and comes with six o-rings for a better fit on the hitch receiver. The o-rings are removable, so you can adjust the length of the pin based on your hitch.

With push-to-lock technology, you’ll know when this hitch pin is fully locked. It uses an exclusive mechanism from Connor Trailer intended to be a frustration-free design, auto locking into your hitch receiver and allowing you to take the key out after unlocking.

There is also an all-weather rubber cap that provides extra protection against corrosion and grime in extreme weather.

6. Trimax UMAX50 Premium Die-Cast Dual Purpose Coupler Lock

trimax umax50 universal die cast dual purpose coupler lock

Designed as a “one size fits all,” Trimax offers a premium die-cast coupler lock with a dual ratchet lock system. The exclusive design provides 360 degrees of hardened steel protection with a rust-proof hammer tone epoxy finish. The UMAX50 can be used with 1 7/8-, 2-, to 2 5/15-inch couplers and features a keyhole cover that slides up to keep out dirt and grime.

This product costs is a bit more than some of the competition but it comes with a full lifetime guarantee.

7. Master Lock Trailer Lock

master lock trailer hitch lock

This trailer lock from Master Lock is designed to fit most trailer couplers, ranging from 1 7/8 inch to 2 5/16 inch. It features an advanced mechanism that provides resistance to picking and prying and comes with a limited lifetime warranty for peace of mind. This product is “keyed alike,” which means they all use the same key. So if a thief has access to the key, there’s a good chance they’ll be able to easily unlock this trailer lock. The benefit to “keyed alike” products is that one key will unlock all your Master Lock locks, but it’s a strange price to pay for convenience.

This trailer lock is a solid, heavy duty product that is well built and durable. So long as a potential thief doesn’t have access to a key, it’s one of the toughest locks to break off.

8. Connor Trailer Hitch/Receiver Lock

connor black and nickel swivel head receiver lock

Another option from Connor Trailer is this hitch lock, that comes with both 1/2- and 5/8-inch pins. Like the other Connor Trailer product on this list, these pins feature a black nickel finish and are designed to work with all Class I/II 1 1/4 inch by 1 1/4 inch hitches, Class III/IV/V 2 inch by 2 inch and 2 1/2 inch by 2 1/2 inch receivers. The smaller pin is capable of towing up to 3,500 gross trailer weight (GTW), while the long pin supports up to 20,000 GTW. The small pin has 2 7/8 inch of usable length, while the long pin offers 3 1/2 inch of usable length.

These pins have the same push-to-lock feature as the other Connor Trailer product, which also allows you to take out the key after unlocking. It has a 360-degree locking head for convenience, along with an all-weather rubber cap to provide extra protection against corrosion and grime in extreme weather conditions.

Manufactured from heavy duty solid steel, these pins offer superior strength to go with its durable black nickel finish.

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9. Trimax UMAX100 Premium Universal Solid Hardened Steel Trailer Lock

trimax umax100 premium universal trailer lock

An even heavier duty option from Trimax is the company’s UMAX100 universal coupler lock. Like the UMAX50, the UMAX100 features a 9/16-inch shackle and offers 360 degrees of solid hardened steel with a patented dual purpose coupler lock. Designed to fit most couplers from 1 7/8 inch to 2 5/16 inch, the UMAX100 takes protection to a new level with a ballistic grade nylon housing that can absorb hammer blows, while also giving it protection against harsh weather conditions.

The nylon housing also incorporates a keyhole cover to keep out dirt and grime. This coupler lock features a type A key, which is a spring loaded, seven-pin high security key. This helps resists attempted drill outs.

Trimax offers a lifetime warranty on all their products.

10. Tow Ready GorillaGuard Coupler Lock

tow ready gorilla guard coupler lock

For a more affordable option, take a look at the Tow Ready GorillaGuard coupler. This product is designed to shield the lock from tampering devices and fits most 2-inch couplers. According to the company, this coupler will only work on coupler widths (including lip) with a diameter of 3 13/16 inches or smaller, while the height of the coupler lip cannot exceed 5/16 inch.

This is a surround lock that is keyed unique, which means you don’t have to worry about a thief potentially having the same key. It is designed to protect unattended trailers, but it also tow ready.

The Tow Ready GorillaGuard comes with two keys and a one-year limited warranty.

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What is a Hitch or Trailer Lock?

As their name suggests, a hitch or trailer lock is designed to keep your trailer from getting stolen. A hitch lock is a product that keeps your trailer hitch and receiver together, with the lock preventing someone from lifting the receiver. This ensures that a thief isn’t able to unhitch the trailer unless the lock is off.

A trailer lock, also known as a coupler lock, keeps your trailer safe when it’s unhitched from your vehicle. Without a coupler lock, someone can simply drive up to your trailer, hitch it, and drive off. These locks fit over the coupler on the trailer’s tongue, preventing someone from hooking up their vehicle and driving off.

Essentially, a hitch or trailer lock plays the role of an insurance policy. Without one of these locks, a savvy thief can drive off with your trailer in a matter of minutes, if not seconds. Unfortunately there is no such thing as a lock that will completely prevent a thief from stealing your property if they want it badly enough and have the time to break off the lock. But locks do serve as a deterrent and some may cause enough of a struggle that the thief gives up.

What to Look for When Shopping for a Hitch or Trailer Lock

Before you start shopping, you’ll need to determine your hitch class if you’re shopping for a hitch lock. Hitches range from Class I to Class V, and not all hitch locks will support up to Class V hitches. Generally, most trailer locks are either 1/2- or 5/8-inch pins and you’ll need to make sure the lock works with your hitch before purchasing. Generally, Class II hitches use 1/2-inch pins, while Class III to Class V hitches use 5/8-inch pins.

When shopping for a hitch or trailer lock, you’ll want to pay close attention to the material it’s constructed from. You will ideally want to purchase a product made from high quality steel, or even hardened steel. Softer metals like aluminum may be lightweight, but they’re easy to damage, allowing a thief to simply take a hammer to your lock.

The next important factor is seeing whether the lock uses a unique key, or if the key design is shared across an entire product’s lineup. Naturally you will want a product that is uniquely keyed, so you don’t have to worry about a thief potentially having a key to your lock.

Depending on where you live and your weather conditions, make sure you invest into a lock that can withstand harsh weather conditions. Some products will corrode and rust quicker than others, potentially causing the lock to seize up. Check user reviews if you live in an area that sees snow or rain, as a rusted keyhole will cause you many headaches. At the very least, make sure you purchase a product that has a weatherproof cap for the keyhole.

If you’re purchasing a trailer or coupler lock, make sure it fits your exact application. Although many products are advertised as being universal, some may not work with certain trailers or hitches. Check user reviews or contact the manufacturer to confirm a particular product works with your specific application.


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