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Best Trailer Hitch Locks

Secure your trailer from potential theft with one of the best trailer hitch locks.
Written and Tested By:
Ben Kasierski
Written and Tested By: Ben Kasierski Contributor – Motor1 Review Team

Ben Kasierski is a North Carolina native who covers the latest automotive and motorcycle products. He has tested hundreds of car detailing products – including tire shines,  car wash soaps, and full detailing kits – as well as gadgets to make life easier for the everyday driver like key finders and GPS trackers.

Last Updated 01/04/2024

Motor1 Reviews Team Take:

  • The best trailer hitch locks in 2024 are the MasterLock Universal 389-DAT, Reese Towpower Coupler Lock, MasterLock 377-DAT, Curt ⅝-inch Pin Lock, and Reese Towpower Heavy-Duty Lock.
  • Most trailer hitch locks cost between $20 and $30. Costlier locks tend to be made of sturdier materials.
  • Rust- and corrosion-resistant trailer hitch locks backed by long warranties tend to last the longest.
Best Trailer Hitch Lock
MasterLock Universal 389-DAT

A top Amazon pick with unbeatable value.

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Runner-Up
Reese Towpower Coupler Lock

An adjustable lock with bright warning colors.

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Best
Lock Design
MasterLock 377-DAT

A trailer tongue lock with adjustable options.

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Best
Locking Hitch Pin
Curt 5/8-Inch Pin Trailer Hitch Lock

A high-quality hitch pin lock for any 2.0-inch receiver.

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Best
Heavy-Duty
Reese Towpower Heavy-Duty Lock

A very sturdy upgrade to ward off tough opponents.

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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 prevent your trailer from being coupled to another vehicle. There are many good reasons to use such a lock, with peace of mind being the first and foremost. And at a 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.


Trailer Hitch Lock Reviews

Best Trailer Hitch Locks

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 prices.

The 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 its value. Each trailer hitch lock was given a rating out of 5.0 stars based on these criteria.

What Is The Best Trailer Hitch Lock?

We named the MasterLock Universal 389-DAT, Reese Towpower Coupler Lock, MasterLock 377-DAT, Curt ⅝-inch Pin Lock, and Reese Towpower Heavy-Duty Lock as the best-rated trailer hitch locks on the market in 2024.

Brand/ModelCostOverall RatingAward
MasterLock Universal 389-DAT$285.0Best Trailer Hitch Lock
Reese Towpower Coupler Lock$164.7Budget Pick
MasterLock 377-DAT$334.7Best Fitting
Curt ⅝-Inch Pin Trailer Hitch Lock$204.5Best Locking Hitch Pin
Reese Towpower Heavy-Duty Lock$454.5Best Heavy-Duty Lock

*Because cost data fluctuates, the prices in the table above are approximate values that our team regularly updates.

Trailer Hitch Lock Ratings: Our Testing Process

After looking at factors such as lock design, customer ratings, and prices, our product testing team ordered the trailer hitch locks that best met these standards. A team member tested each product, taking note of value, fit, and accessibility. Each trailer hitch lock was given a rating out of 5.0 stars based on these criteria.

Learn more about how we tested trailer hitch locks in our full testing methodology section here.


1. MasterLock Universal 389-DAT: Best Trailer Hitch Lock

  • Cost: Around $30
  • Amazon review score: 4.7 out of 5.0 based on more than 15,000 ratings
  • Fit: 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

MasterLock Universal 389-DAT Review

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.

You can see how the MasterLock Universal 389-DAT performed in each of our testing categories below: 

Review CategoryScore (Out of 5.0 Stars)
Value5.0
Fit5.0
Accessibility5.0
Overall Rating5.0

Below are the pros and cons of the MasterLock Universal:

Pros Sturdy materials Great price Easy to open and close
Cons Keys are not unique

MasterLock Universal 389-DAT: Our Experience

Based on our experience, we rated the MasterLock Universal 389-DAT lock at 5.0 out of 5.0 stars. It is strongly built but also accessible in a pinch, plus we admire 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 drawback, however, is the keys to the 389-DAT are not unique, so there is a possibility that a key from another 389-DAT could open your lock.

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.

The MasterLock Universal 389-DAT attached and installed to a trailer hitch.

MasterLock Universal 389-DAT: What Customers Are Saying

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.


2. Reese Towpower Coupler Lock: Budget Pick

  • Cost: Around $15
  • Amazon review score: 4.6 out of 5.0 based on more than 16,900 reviews
  • Fit: Most 1 7/8-, 2.0-, and 2 5/16-in. couplers
  • Aluminum body and heavy-duty steel lock bar
  • Adjustable ratchet design
  • Bright yellow theft-deterrent color
  • One-year limited warranty

Reese Towpower Coupler Lock Review

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.

You can see how the Reese Towpower Coupler Lock performed in each of our testing categories below: 

Review CategoryScore (Out of 5.0 Stars)
Accessibility5.0
Fit4.5
Value4.5
Overall Rating4.7

Below are the pros and cons of the Reese Towpower:

Pros Easy to use Great price point
Cons Material quality could be better Slightly loose fit

Reese Towpower Coupler Lock: 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 loses 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.

The Reese Towpower Coupler Lock attached and installed to a trailer hitch.

Reese Towpower Coupler Lock: What Customers Are Saying

Positive reviews acknowledge the Towpower Coupler as a great theft deterrent. Users are pleased that this lock is easy to use and offers effective security.

One of the most common complaints that customers have about the Towpower Coupler lock is about sizing. Reese insists the distance between the ball mount and lock shackle holes is 4.5 in., yet some Amazon customers say their locks don’t fit due to shorter-than-advertised width.


3. MasterLock 377-DAT: Best Lock Design

  • Cost: Around $30
  • Amazon review score: 4.6 out of 5.0 based on more than 1,700 ratings
  • Fit: Most 1 7/8-, 2.0-, and 2 5/16-in. couplers
  • Zinc nickel-plated body for reduced rust and corrosion
  • Front access keyway
  • Advanced locking mechanism
  • Limited lifetime warranty

MasterLock 377-DAT Review

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 willing to spend a few extra bucks for increased durability and a stable fit.

You can see how the MasterLock 377-DAT performed in each of our testing categories below: 

Review CategoryScore (Out of 5.0 Stars)
Accessibility5.0
Fit5.0
Value4.0
Overall Rating4.7

Below are the pros and cons of the MasterLock 377-DAT:

Pros Adjustable locking positions Secure fit
Cons Also can be accessed with same lock keys A bit pricey

MasterLock 377-DAT: Our Experience

The 377-DAT earned a rating of 4.6 stars for its accessibility and comfortable fit. It is 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.

The MasterLock 377-DAT attached and installed to a trailer hitch.

MasterLock 377-DAT: What Customers Are Saying

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.


4. Curt 5/8-Inch Pin Trailer Hitch Lock: Best Locking Hitch Pin

  • Cost: Around $20
  • Amazon review score: 4.5 out of 5.0 based on more than 16,400 ratings
  • Fit: 5/8-in. diameter pin with nearly 3.0-in. usable pin length
  • Barbell-style body
  • Fits 2.0-in. receivers
  • Watertight keyhole dust cap
  • Black powder coat finish
  • Limited lifetime warranty

Curt ⅝-Inch Pin Trailer Hitch Lock Review

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.

You can see how the Curt ⅝-Inch Pin Trailer Hitch Lock performed in each of our testing categories below:

Review CategoryScore (Out of 5.0 Stars)
Accessibility4.0
Fit4.5
Value5.0
Overall Rating4.5

Below are the pros and cons of the Curt 5/8-Inch Pin Trailer Hitch Lock:

Pros Simple design Sturdy materials
Cons Difficult to remove Scratches easily

Curt ⅝-Inch Pin Trailer Hitch Lock: Our Experience

While the Curt Hitch Pin installs with no fuss and has an incredibly simple yet sturdy design, it is difficult to remove and scratches easily. We 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.

A close-up image of the Curt 5/8-Inch Pin Trailer Hitch Lock.

Curt ⅝-Inch Pin Trailer Hitch Lock: What Customers Are Saying

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 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.


5. Reese Towpower Heavy Duty: Best Heavy-Duty Lock

  • Cost: Around $45
  • Amazon review score: 4.4 out of 5.0 based on more than 4,200 ratings
  • Fit: 5/8-in. diameter pin with nearly 3.0-in. usable pin length
  • Barbell-style body
  • Fits 2.0-in. receivers
  • Watertight keyhole dust cap
  • Black powder coat finish
  • Limited lifetime warranty

Reese Towpower Heavy Duty Review

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.

You can see how the Reese Towpower Heavy Duty performed in each of our testing categories below: 

Review CategoryScore (Out of 5.0 Stars)
Accessibility4.0
Fit5.0
Value4.5
Overall Rating4.5

Below are the pros and cons of the Reese Towpower Heavy Duty:

Pros Extremely durable Fits most trailers easily
Cons Difficult to take off Might get weather-damaged

Reese Towpower Heavy Duty: Our Experience

Our review team gives 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 is 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.

The Reese Towpower Heavy Duty attached and installed to a trailer hitch.

Reese Towpower Heavy Duty: What Customers Are Saying

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.


Trailer Hitch Lock Buying Guide

Before you start shopping for trailer hitch locks, it can be helpful to know about the different types of locks, materials, and more.

Compare Trailer Hitch Locks

Brand/ModelFitWarranty
MasterLock Universal 389-DAT1 7/8″; 2.0″; 2 5/16″Lifetime
Reese Towpower Coupler Lock1 7/8″; 2.0″; 2 5/16″One-year
MasterLock 377-DAT1 7/8″; 2.0″; 2 5/16″Lifetime
Curt ⅝-Inch Pin Trailer Hitch Lock5/8″ diameter pinLifetime
Reese Towpower Heavy-Duty Lock1 7/8″; 2.0″; 2 5/16″One-year

What Is A Trailer Hitch Lock?

Trailer hitch locks are designed to prevent thieves from stealing your trailer by attaching the hitch to their own vehicle. There are three types of trailer hitch 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 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.
Lock Material

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.

Size

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-in. 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.

Best Trailer Hitch Locks: Bottom Line

Trailer Hitch Lock: FAQ

Below are some common frequently asked questions about trailer hitch locks:

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.

Full Trailer Hitch Lock Testing Methodology

We tested each trailer hitch lock by connecting it to a trailer hitch, testing the fit, and removing the lock. In handling each lock, we assessed both fit and accessibility.

Fit

Our fit score represents how well each lock fits the trailer hitch. Those that fit snugly with no rattling earned more points in this category. Locks that were loose, jangly, or could be maneuvered on the hitch while attached lost points in this category.

Accessibility

Our accessibility rating is based on how easy the lock is to remove using its given set of keys. Locks with easily accessed keyholes that open fluidly score best in this category. Locks use points if the keys do not function smoothly or the keyhole is difficult to access.

Value

Each lock’s value is based on its performance as a lock as well as how long it can be expected to last. Trailer hitch locks score better in this category if they include long warranties, are made from durable materials, and are relatively low-cost.

How We Score Products

Every trailer hitch lock we test is given a score between 1.0 and 5.0 stars in each category. Here’s what those star ratings mean in concrete terms:

  • 5.0 Stars: A 5.0-star rating means a trailer hitch lock is among the best in a category. It can be attached and removed seamlessly, or it is made with corrosion-resistant materials and backed by a lifetime warranty.
  • 4.0 Stars: A 4.0-star rating means a trailer hitch lock performs better than average in a category. It can be attached and removed without effort, is made with strong materials, is backed by a 5+ year warranty, or is relatively inexpensive.
  • 3.0 Stars: A 3.0-star rating indicates what is average or typical for a trailer hitch lock, based on our testing experience. It can be attached and removed reliably, but with some effort, or is averagely-priced given the materials and warranty.
  • 2.0 Stars: A 2.0-star rating indicates the trailer hitch lock performs poorer than the average silicone wiper blade. It is hard to install and remove or it is especially expensive considering the materials.
  • 1.0 Star: A 1.0-star rating indicates that the trailer hitch lock performs well below expectations in a category. It does not fit most trailer locks, is very difficult to remove, or is unlikely to deter theft.

Why Trust Motor1.com

Each year, we test over 350 auto products on vehicles and in our testing lab. Our team of product testers thoroughly researches top products, unboxes and puts our hands on each component, and tests the items on real vehicles before making recommendations to readers.

We publish hundreds of product and service reviews to bring car enthusiasts detailed guides on automotive tools, detailing kits, car seats, pet products, and much more. For more information on our testing methodology and how we evaluate every product, check out our methodology page here.

*Data accurate at time of publication. Products subject to availability.