Imagine you’re on a camping trip and you’ve come back from a hike only to discover your mobile trailer is gone. Unfortunately, trailers are still susceptible to theft like any other item, but this is where the best trailer hitch locks can come to the rescue. Trailer hitch locks offer added protection by preventing your trailer from being coupled to another vehicle. There are many good reasons to attach one to your trailer, with peace of mind being the first and foremost. And at the fraction of the cost of replacing a trailer, investing in a great trailer hitch lock has long-term benefits.
Our product review team has tested and reviewed the top five best trailer hitch locks on the market. We break down everything from fit to durability to give you the most comprehensive review possible. Although many locks act as a preventative measure, no lock is absolutely theft-proof and each has its pros and cons.
In this article:
- 5 Best Trailer Hitch Locks
- #1 Best Overall: MasterLock Universal 389-DAT
- #2 Runner-Up: Reese Towpower Coupler Lock
- #3 Best Lock Design: MasterLock 377-DAT
- #4 Best Locking Hitch Pin: Curt 5/8-Inch Pin Trailer Hitch Lock
- #5 Best Heavy-Duty: Reese Towpower Heavy Duty
- Best Trailer Hitch Locks Buyers Guide
- Our Review Standards
- Frequently Asked Questions
5 Best Trailer Hitch Locks
#1 Best Overall: MasterLock Universal 389-DAT
MasterLock has cemented itself as one of the best lock brands in the automotive industry, and its Universal 389-DAT only solidifies its spot. It's a universal fit, so this lock pairs with various 1 7/8-, 2.0-, and 2 5/16-inch coupler sizes. The exterior of the lock is chrome to prevent rust and corrosion while its forged steel body improves both security and longevity. And its bright red finish may deter any would-be thief from wanting to come anywhere near it.
Although the 389-DAT’s advanced locking system prevents picking and prying, users can easily secure and remove the lock with the included keys. MasterLock even provides a limited lifetime warranty on their locks, guaranteeing a full refund in an event where a lock may not have been a strong enough deterrent.
Key Features
- Fits most 1 7/8-, 2.0-, and 2 5/16-inch couplers
- Rust and corrosion-resistant
- Bright red deterrent color
- Limited lifetime warranty
- Can be purchased in one-, three-, or four-pack
Our Experience
Based on our experience, we rated the MasterLock Universal 389-DAT lock at 5 out of 5 stars. It was strongly built but also accessible in a pinch, plus we admired its ease of use and security at a competitive price.
- Accessibility: Using the provided keys, the 389-DAT opened and closed with little hassle. We had no problems attaching and removing the lock from our trailer coupler. A minor drawback, however, is the keys to the 389-DAT are not unique, so anyone with the same lock can access others.
- Fit: The 389-DAT fit snugly to our coupler and required little adjustment to create a sealed lock.
- Value: Made with forged steel and chrome, the 389-DAT is made of sturdy materials yet didn’t break the bank.
| Overall Rating | 5 out of 5 |
|---|---|
| Accessibility | 5 out of 5 |
| Fit | 5 out of 5 |
| Value | 5 out of 5 |
What Customers Are Saying
On Amazon, the 389-DAT is currently the number one bestseller in towing hitch locks and Amazon’s Choice for the search term “master lock universal trailer coupler lock.” It maintains an average review score of 4.7 out of 5 stars from close to 11,000 ratings. Even more in the 389-DAT’s favor, less than 10 percent of all review scores are 3 stars or lower.
Most of the positive reviews focus on the 389-DAT’s easy installation. There are also a high number of customers who claimed thieves attempted to steal their trailers but couldn’t due to the 389-DAT’s superior durability. Despite the high number of positive ratings, negative reviews highlighted the 389-DAT’s poor performance in harsh wintry environments.
What Is It Good For?
The MasterLock Universal 389-DAT is the ideal choice for anyone who needs to securely park their trailer and wants peace of mind when doing so. And with its steel construction at a reasonable price, the 389-DAT provides unmatched security.
#2 Runner-Up: Reese Towpower Coupler Lock
Even at its incredibly low price, the Reese Towpower Coupler Lock outperforms most other hitch locks on the market. The steel lock bar is nearly impenetrable while the bright yellow color warns would-be thieves to stay away. Its U-shaped design is very simple to install, plus offers various fits thanks to its 11 adjustable positions.
The Towpower Coupler fits most 1 7/8-, 2.0-, and 2 5/16-inch couplers, making it universally versatile. While it may stand strong against a lockpicker’s arsenal, the keys are unfortunately not unique to each lock and can open other ones of the same model.
Key Features
- Fits most 1 7/8-, 2.0-, and 2 5/16-inch couplers
- Aluminum body and heavy-duty steel lock bar
- Adjustable ratchet design
- Bright yellow theft-deterrent color
- One-year limited warranty
Our Experience
We had a positive experience with the Towpower Coupler, which led us to rate it at 4.7 stars. It has many similarities with our top overall pick for best trailer hitch locks but lost some points for its materials and fit.
- Accessibility: The Towpower Coupler’s adjustable arm made fastening the lock to our trailer quick and painless. Both keys worked well, too.
- Fit: Despite the Towpower Coupler’s ratchet arm, it did not fit as snugly to our hitch as we had hoped. It rattled slightly since the trailer ball was a bit small for the receiver, yet was nowhere close to being removable.
- Value: While its price is extremely competitive with other locks, the body of the Towpower Coupler is aluminum. This metal is more prone to weather damage and scratching than others, so its long-term value may not be as high as locks made with stainless steel.
| Overall Rating | 4.7 out of 5 |
|---|---|
| Accessibility | 5 out of 5 |
| Fit | 4.5 out of 5 |
| Value | 4.5 out of 5 |
What Customers Are Saying
The Towpower Coupler currently reigns as Amazon’s Choice for the search term “trailer hitch locks with keys.” It has an average review score of 4.6 stars, which is considerably high given that it has over 14,000 ratings. Nearly 80 percent of these ratings are 5 stars as well.
One of the most common reviews that customers leave is that their Towpower Coupler locks did not fit as advertised. Reese insists the distance between the ball mount and lock shackle holes is 4.5 inches, yet Amazon customers say their locks don’t fit due to shorter-than-advertised width. Positive reviews, on the other hand, acknowledge the Towpower Coupler as a great deterrent.
What Is It Good For?
Reese is a dependable name in the lock industry, so it stands to reason that the Towpower Coupler Lock is a worthwhile investment. This lock should help prevent anyone from tampering with your trailer.
#3 Best Lock Design: MasterLock 377-DAT
The MasterLock 377-DAT may look like something from the distant future, but its present-day security is very real and very strong. Its gray zinc nickel-plated body reduces rust and corrosion even in the toughest elements.
The 377-DAT has a front access keyway with three adjustable positions that make installation a breeze. This doesn’t compromise its advanced locking system, either.
Key Features
- Fits most 1 7/8-, 2.0-, and 2 5/16-inch couplers
- Zinc nickel-plated body for reduced rust and corrosion
- Front access keyway
- Advanced locking mechanism
- Limited lifetime warranty
Our Experience
The 377-DAT earned a rating of 4.6 stars for its accessibility and comfortable fit. It was relatively expensive compared to other locks.
- Accessibility: The front access keyway and adjustable locking positions made attaching the device to our trailer no problem. Unfortunately, like the other locks we tested, the 377-DAT can be accessed by anyone who bought the same lock and has keys.
- Fit: The adjustable setting on the 377-DAT made securing a tight fit incredibly easy. Once attached properly, we weren't able to slide the lock around or move it in any way.
- Value: The 377-DAT is a bit more expensive than other locks of similar value. Its zinc body may be strong but is more susceptible to wear and tear over time.
| Overall Rating | 4.7 out of 5 |
|---|---|
| Accessibility | 5 out of 5 |
| Fit | 5 out of 5 |
| Value | 4 out of 5 |
What Customers Are Saying
The 377-DAT is currently Amazon’s Choice for the search term “master lock 377” and has over 1,100 ratings. Its review score is 4.6 stars, with nearly 90 percent of customers leaving a score of 4 stars or higher.
There are countless positive reviews that praise the 377-DAT’s strength. Some customers even claim to have caught potential thieves unsuccessfully attempting to steal their trailers because the 377-DAT wouldn’t budge against hammer blows. A few of the negative reviews wished the 377-DAT had chrome plating instead of zinc for extra protection against the weather.
What Is It Good For?
The MasterLock 377-DAT is perfectly designed for easy access and a very tight fit with little adjustments. Our product review team recommends this lock to anyone who’s willing to spend a few extra bucks for increased durability and a stable fit.
#4 Best Locking Hitch Pin: Curt 5/8-Inch Pin Trailer Hitch Lock
When you’re on the go with your trailer and don’t want to detach it from your vehicle, a locking hitch pin fastens the two together so thieves can’t separate them. The Curt 5/8-Inch Pin Trailer Hitch Lock has a reinforced carbon steel body that makes it an ideal theft deterrent. Its black powder coat and watertight keyhole dust cap are weather-resistant for almost any condition.
The Curt Pin Hitch’s locking head can be unlocked with a quarter-turn of the key for easy access, making it one of the best trailer hitch lock options. And because it installs into a vehicle’s receiver, there’s minimal risk of this lock being thwarted by bolt cutters.
Key Features
- 5/8-inch diameter pin with nearly 3.0-inch usable pin length
- Barbell-style body
- Fits 2.0-inch receivers
- Watertight keyhole dust cap
- Black powder coat finish
- Limited lifetime warranty
Our Experience
While the Curt Hitch Pin installed with no fuss and had an incredibly simple yet sturdy design, it was difficult to remove and scratched easily. This led us to give it a 4.5-star rating overall.
- Accessibility: Linking the Curt Hitch Pin Lock through our trailer mount wasn’t very difficult, and the pin locked easily. When trying to remove it, though, the lock wouldn’t come unfastened and required a few tries before we were able to get it off. Like the other locks in this review, it can be accessed with keys purchased from the same model.
- Fit: This lock was not adjustable, so it’s one-size-fits-all or bust. It fit effortlessly into our trailer receiver but did have some wiggle room that caused rattling.
- Value: In terms of price, the Curt Hitch Pin is reasonable. Its carbon steel body is incredibly strong as well as rust and corrosion-resistant, so it should have a long life.
| Overall Rating | 4.5 out of 5 |
|---|---|
| Accessibility | 4 out of 5 |
| Fit | 4.5 out of 5 |
| Value | 5 out of 5 |
What Customers Are Saying
The Curt Hitch Pin has around 13,000 ratings for an average review score of 4.5 stars. It’s also currently Amazon’s Choice for the search term “hitch locks with keys.” Almost 90 percent of all ratings were 4 stars or above, while only 5 percent were 1 star.
A common subject among the reviews is not the quality of the lock, but the keys that come with it. There are multiple complaints that the keys are made of plastic and break off too easily inside of the Curt Hitch Pin when trying to lock it. Other reviewers are not happy with the dust cover, which they also say fell off of their locks quickly after buying. Some reviews claim that adding O-washers to each side of the lock improves its fit significantly.
What Is It Good For?
The Curt 5/8-Inch Pin Trailer Hitch Lock can keep your camper or travel trailer safely secured for parking overnight. The unlocking mechanism can be sticky, though, so be careful when detaching it.
#5 Best Heavy-Duty: Reese Towpower Heavy Duty
A popular upgrade to the Reese Towpower Coupler Lock, the Reese Towpower Heavy-Duty Lock adds a few extra features to improve security. Its aluminum body, for example, is filled for a heavier weight than its hollow counterpart. The Heavy-Duty Lock also has a much thicker steel arm for increased durability.
All things considered, the Heavy-Duty Lock does share many likable features with the Reese. For example, it also has universal compatibility, 11 adjustable locking positions, and a 1-year limited warranty. Both are theft-deterrent colors, but the Coupler’s yellow burns a bit brighter than the Heavy-Duty’s silver coat.
Key Features
- Fits most 1 7/8-, 2.0-, and 2 5/16-inch couplers
- 11 adjustable locking positions
- Aluminum body and heavy-duty steel lock bar
- Bright silver theft-deterrent color
- One-year limited warranty
Our Experience
Our review team gave the Heavy-Duty Lock a 4.5-star rating for its hefty design. It was very difficult to take off of our testing trailer due to its sticky keyhole, but its superior strength was worth noting.
- Accessibility: Bolting the Heavy-Duty Lock to our trailer was easy, but removing it proved to be a challenge. The keys got easily jammed and took careful finagling before we could safely remove them without damaging the lock. This lock can also be accessed by anyone who has a key from the same model.
- Fit: This lock fit snugly over the receiver and was able to secure a tight fit thanks to its thick steel arm. The hitch ball was still slightly too small.
- Value: Its price competes with those of similar locks, but it has an aluminum body that may not hold as well over time. This means the Heavy-Duty lock is also prone to weather damage if not treated properly.
| Overall Rating | 4.5 out of 5 |
|---|---|
| Accessibility | 4 out of 5 |
| Fit | 5 out of 5 |
| Value | 4.5 out of 5 |
What Customers Are Saying
The Heavy-Duty Lock currently has around 3,200 ratings on Amazon with an average review score of 4.5 stars. Over 75 percent of these are 5-star ratings.
Top reviews for the Heavy-Duty Lock are mixed. Some customers believe it to be a very well-designed lock that offers improved protection against thieves, while others claim their locks broke on first use. The most common complaint is about the quality of the keys and locking mechanism. However, the vast majority of reviews are positive and praise the Heavy Duty Lock’s construction.
What Is It Good For?
For an upgrade to the Coupler, the Reese Towpower Heavy-Duty Lock is our top pick. It’s designed to withstand nearly any attempt to break it and is backed by the Reese name for quality assurance.
Best Trailer Hitch Locks Buyers Guide
Before you start shopping for trailer hitch locks, it can be helpful to know about the different types of locks, materials, and more.
What Is A Trailer Hitch Lock?
Trailer hitch locks are designed to prevent thieves from stealing your trailer by attaching to your trailer hitch. A trailer hitch is generally the part that attaches a trailer to a vehicle, and we recently published a roundup of the best trailer hitches.
There are three types of locks: coupler, pin, and wheel. Coupler hitch locks lock into the receiver on a trailer so a trailer cannot be attached. A pin or receiver hitch lock, on the other hand, secures the receiver to the trailer hitch so the two can’t be separated. Wheel locks act as a boot that prevents a trailer from rolling.
Many trailer hitch locks are made of heavy-duty steel or other corrosion-resistant metals to improve security and durability. Locks made with materials such as aluminum should be considered carefully because of their potential to rust when exposed to grime and other contaminants, which decreases their strength.
Unlike combination padlocks, trailer hitch locks are secured with a unique key. The most common hitch locks are designed to fit 1 7/8-, 2.0-, and 2 5/16-inch trailer hitch mounts. These are generally Class I or II trailers, but most of these are designed to fit Class III and above, as well.
Our Review Standards
The trailer hitch locks in this article went through two rounds of reviews. We started by searching Amazon for top products, looking at factors like Prime shipping eligibility, customer ratings, Amazon superlatives, and price.
The five locks that best met these standards were ordered by our team for testing. A team member tested each product on a car, taking note of how well the lock fit our trailer, its accessibility, and value. Each trailer hitch lock was given a rating out of five stars based on this criteria.
Trailer Hitch Locks Testing Process
The following characteristics were used to rate each lock during our testing process:
- Accessibility: This measured how easily the trailer hitch lock opened or closed using its given set of keys. We also determined how difficult it was to try and take each lock from our trailer.
- Fit: Based on how snugly each lock fit to our trailer hitch, it earned more points. Locks that were loose, jangly, or could be maneuvered on the hitch while attached lost points.
- Value: Each lock’s materials, price, and warranty were researched to determine if they held their value over time. Locks made of more durable materials and were offered at a lower price than others gained points.
Frequently Asked Questions
What are the best trailer hitch locks made of?
Dependable trailer hitch locks are built with heavy-duty materials such as stainless steel, forged steel, chrome, or similar metals. These work best not only because they’re tough to break, but can repel water for improved rust and corrosion resistance.
What’s the difference between a coupler lock and a receiver lock?
A coupler lock attaches to the coupler of a trailer to prevent it from being attached to anything else. A receiver lock hitches to the receiver to prevent a trailer from being separated from its tow vehicle. Coupler locks are generally larger than receiver locks and more expensive but can protect your trailer when it stands alone.
How do I know if a trailer hitch lock will fit my trailer?
Many trailer hitch locks on the market are known as universal coupler locks, which are designed to fit almost any 1 7/8-, 2.0-, and 2 5/16-inch mounts. Odds are if you have a trailer for day-to-day use such as transporting boats or small campers, these locks will fit. Always check your trailer’s guide, though, to be sure your trailer fits these required measurements.
*Data accurate at time of publication.
