Best U Lock Reviews 2023

Are you searching for a top-notch U-lock that will safeguard your bike, but don’t have the time or energy to go through reviews or compare products to aid your search? No need to worry, that’s our job – to do the grunt work and make life easier for you. Here we present 5 top brands with the best U-locks that made it to our list after a rigorous analysis, involving numerous brands with U-locks in the market. While we reviewed one product per brand in this review, you should also note that the featured brands have plenty of other U-lock models, and we invite you to take a look at them as well.
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Lock Type
Our Top Choice
OnGuard Bulldog DT
OnGuard Lock, like a dog with a bone, relentlessly obsesses about security so that its customers don’t have to.
Thick bar and cable. Heavy-duty, secure, and weatherproof. Easy-to-use keys and cable for extra security.
Its locking mechanism is somewhat tedious.
Braided steel
11.6 x 7.8 x 2.2 inches; 1 lbs
11mm (0.43 inches)
Shackle and steel cable
Best Value
Sigtuna Gear 16mm Bike Lock + Cable Combo
Sigtuna Gear is made up of a team of bike-loving Swedes committed to making prime-quality bicycle gear.
Strong, heavy-duty bike security. Easy to use and attach to the bike. Comes with detailed instructions.
This U-lock is a little heavy.
9.4 x 7 x 1.9 inches; 3.1 lbs
16mm (0.63 inches)
Double bolt mechanism
Kryptonite New York Fahgettaboudit Mini
Kryptonite was created to employ innovative solutions to enable bikers to protect what they value, keeping it safe from people who would steal it.
Strong, heavy-duty, and small in size. Difficult to forcefully open. High-quality and appraised.
The lock is surprisingly heavy.
2 x 5.7 x 9.2 inches; 4.4 lbs
18mm (0.71 inches)
Double deadbolt locking
ABUS Yellow Mini 40 U-Lock
Abus is a leading brand when it comes to matters of security and has become synonymous with thief-proof protection.
Lightweight, high-security lock can be carried on your belt or in your pocket. Buttery smooth locking mechanism.
It doesn’t come with a mounting bracket.
Hardened steel
5.1 x 7.2 x 1.4 inches; 2 lbs
14mm (0.55 inches)
Double bolt mechanism
Cocoweb ARMBAR Heavy Duty U-Lock
Cocoweb creates products that receive rave reviews, and its U-lock combo packs aren’t exempted, as it’s been known to produce efficient locks.
Affordable, high-level security U-lock. Locks both tire and frame to a post. Lock and mount are PVC-coated.
Its customer support could be better.
Alloy steel
2.5 x 11 x 7 inches; < 3 lbs
15mm (0.6 inches)
Quick snap carrier

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Watch Our U Lock Review

What is the Best U Lock?

U-locks possess various attributes that make them the lock of choice for bikes. Having read our informative buying guide to the end, it’s safe to assume that you’re in a much better position to make an informed choice from the featured U-locks in our individual product review section. So, go ahead and take a look at the products we picked and reviewed for you.
Our Top Choice
The Bulldog DT U-Lock from OnGuard is a 9-inch shackle that’s combined with a 4-foot braided steel cable. It comes with five laser-cut keys (4 extra-grips and a micro-light key with a built-in light). If you’re looking for a smaller-sized U-lock of equal quality, have a look at the OnGuard Bulldog Mini DT U-Lock with a 4-foot loop cable.

OnGuard Bulldog DT U-Lock with 4-Foot Cinch Loop Cable

OnGuard is a maker and distributor of security products for bicycles, motorcycles, and power sports in general. It was founded in 2002 to deliver the best locks at the most competitive prices. Its locks are designed to offer optimal feature-advanced technological innovation thus equipping them to offer the highest security and convenience. It understands that not all security needs are the same and makes its locks in three categories so you get to choose the lock that best suits your need. In the ‘unhoped-for’ event of key loss, this company has a responsive support team and a key registration program that ensures you get replacement keys.

The OnGuard Bulldog DT U Lock gives you security and its attendant peace of mind at a pocket-friendly price. It’s a 9-inch shackle with bars 0.51 inches thick and made of hardened steel. It comes with a super-flexible 4-foot braided steel cable with loops that have been permanently swedged, which increases the versatility of this U-lock as it makes it possible for both wheels on a bike to be locked up. You can also get inventive with the way you choose to combine the cable and the U-lock on your bike. The cable is made of steel and coated all through with a clear vinyl material.

Its locking mechanism secures both sides of the hardened steel shackle to the cross bar, which makes this lock highly resistant to anything a thief may try. It also features the Z-CYL with Bump Lock technology, which renders theft attempts with bump keys futile. The lock mechanism itself is securely encased in super-hardened steel to resist pulling or drilling. This lock can be used for power sports and bikes; what’s more, it has 5 laser-cut keys. One has a built-in LED to help you find the keyhole even in the dark, without needing to feel for it. It also comes with a mounting bracket with which the U-lock can be clipped onto the frame of your bike.

OnGuard has other great U-lock options which include:
  • The OnGuard Bulldog LS U-Lock has a long shackle for more locking options and features the extra-secure X2P double bolt locking mechanism.
  • The OnGuard Pitbull STD U-Lock has a TriRadius hardened steel shackle and X4P locking mechanism takes security to a whole new level.
  • The OnGuard Double-Team PITBULL U-Lock and Cable features an X4P locking mechanism and a 4-foot braided steel cable.
Best Value
The Sigtuna Gear 16mm Bike Lock + Cable Combo features a double bolt mechanism and a braided Flex Cable for added security. Its hardy mounting bracket features a one-button release and Velcro strap. If you’d like a thicker U-lock with a longer cable, the Sigtuna Gear U Lock Shackle with a 5.9-foot braided Flex Cable Lock is also available.

Sigtuna Gear 16mm Bike Lock + Cable Combo with U Lock Shackle & 1200mm Braided Steel Flex Cable

Sigtuna Gear is a brand born out of passion as it proudly declares that “it’s all about the ride”. It was created by a company of Swedish bike-lovers and exists for the sheer love of cycling and the exhilarating feeling it brings. Having experienced the thrills of climbing over majestic mountains and cruising past beautiful beaches, its desire is to ensure that whoever decides to partake of these pleasures has the right gear, the kind dependable enough to make that happen.

The Sigtuna Gear 16mm Bike Lock + Cable Combo features a double bolt mechanism that secures both bars of the 0.6-inch steel U-lock to the crossbar. This design makes it able to withstand pulling, prying, and jacking without so much as a budge.

The 3.9-foot braided Flex Cable is of strong steel and can be used together with the U-lock to extra-secure your bike or lock more than one bike at a time. To use both components on one bike, the manufacturer suggests that the U-lock be put through the back wheel, inside the frame’s rear triangle and secured to something solid. Once the rear wheel has been secured, the cable is then used to lock the front wheel.

It also features a hardy mounting bracket with a one-button release and Velcro strap that makes parking your bike daily as easy as pie. With the hardened steel featured on this U-lock, this unit is built to be long-lasting.

Here’s more U-locks from Sigtuna Gear:
  • The Sigtuna 11mm Mini U-Lock is made of high carbon steel with a double bolt locking mechanism, key hole cover, and two laser-cut Abloy keys. It can be coupled with the chain lock from this company.
  • The Sigtuna 12mm Heavy Duty Chain U-Lock is a Manganese steel chain lock with performance steel shackles, two laser keys, and sleeve covers.
In addition, this U-lock is covered by a 30-day, 100% money-back guarantee.
Kryptonite’s New York Fahgettaboudit Mini is made of 0.71-inch hardened steel and features a high-level security disc-style cylinder. Its center keyway and double deadbolt withstand pulling and leverage attacks. For a lower-budget U-lock with a cable, you should consider the Kryptonite Kryptolok Series 2 Standard Bicycle U-Lock with a 4-foot Flex Cable.

Kryptonite New York Fahgettaboudit Mini U-Lock

For over forty years, the Kryptonite brand has set the pace when it comes to all things bike security. It’s the innovative name behind Bicycle U-lock and is wholly committed to creating globally outstanding security. It’s a brand with a rich history and multiple awards to its name; time and again it’s had open challenges that test the quality of its locks thrown at it—challenges it excelled in. Kryptonite agrees that “thieves suck”, which is one of the reasons it promises to continue reinventing itself and its products to ensure that you’ll always be able to protect a piece of yourself and guard the two-wheeled part of your life.

Kryptonite’s New York Fahgettaboudit Mini features a double deadbolt locking mechanism which gives it a great holding power, and hardened 18mm (0.71-inch) MAX-performance steel that has proven to be resistant to leverage attacks and bolt cutters. Although it’s small, this U-lock is a 4.4-pound pack of dependable bike protection; it’s a heavy-duty lock that’s equipped with the most recent anti-theft technology. Further, its oversized crossbar has a steel sleeve for extra security.

It features a center keyway—another defense against leverage attacks—and a high-level security cylinder that’s styled like a disc. Its protective vinyl coating and sliding dust cover protect the U-lock and extends the life of the cylinder. It has 3 keys, one with a built-in bright intensity LED bulb and replaceable batteries.

Other U-locks from this company are as follows:
  • The Kryptonite Keeper 12 Standard Bicycle U-Lock with Bracket Bicycle U-Lock which features a reinforced collar over the keyway and high-security Bent Foot design for convenient use.
  • The Kryptonite Evolution Mini-5 Bicycle U-Lock with Transit FlexFrame Bracket which has a reinforced cuff over the crossbar and cylinder for extra security.
There’s an anti-theft program that you can join with the purchase of this U-lock.
The ABUS U-Lock Mini 40 features a round ½-inch shackle made of hardened steel with a double bolting lock. It’s corrosion-resistant, bike thief-proof, and comes with 4 keys. If you’d feel better-secured with a larger U-lock, the ABUS Granit X-Plus is also available.

ABUS U-Lock U-Mini 40 – Available in Yellow and Red

ABUS was established in 1924 and has since been providing its customers worldwide with the great feeling that comes with good security. It’s a German manufacturer of high repute that works to ensure that its products are dependable and offer a long, convenient service life. It offers an extensive range of forward-looking solutions for home, mobile, and electronic security. It’s made up of 3 companies, with more than 3500 employees.

The ABUS U-Lock Mini 40 is designed to give you superior protection as it packs a lot into a conveniently small package. It consists of ½-inch hardened steel bars and a double locking cylinder that’s resistant to pulling, prying, or jacking. This U-lock also has a high Sold Secure rating and has been given the “Ice Spray Tested” stamp of approval as well. It features a through-body shackle technology, is torsion-resistant, and is doubly bolted into the lock body.

At 5.5 inches and 2.2 pounds, it’s ergonomically designed to travel with you however you see fit. It has an innovative ‘soft touch’ housing cover that protects it from paintwork damage. Finally, it comes with 4 keys and is available in red and yellow colors.

There are other interesting U-locks from ABUS, some of which are below:
  • The Abus Granit X-Plus 54 Mini is a ½-inch, double-bolting U-lock with an automatic keyhole cover. It comes with 2 keys and one of them has an LED light.
  • The somewhat colorful Abus 410 Ultra Cobra Mini LS is a 0.47-inch round shackle that comes with a cobra cable.
  • The Abus Ugrip 501 Bicycle U-Lock is a ½-inch square shackle which features ABUS power cell patented technology and has a hardened steel body with soft elastomer coating.
  • The Abus Ultimate 420 Bicycle U Lock is a long 0.55-inch shackle with a double-locking mechanism.
The Cocoweb ARMBAR Heavy Duty U-Lock is a 0.55-inch heated alloy steel shackle that features a disc cylinder system. It has a sturdy frame mount with which it can be conveniently attached to your bike. If you’re looking to beef up your bike security with a cable, you ought to have a look at the Cocoweb Heavy Duty Bike Lock, a 4-digit combination lock .

Cocoweb ARMBAR Heavy Duty Anti-theft Bicycle U-Lock – Available in 2 Set Options

The Cocoweb brand brings over 50 years of experience as a major industry player in the manufacturing of the finest home lighting fixtures to bear in the production of its locking mechanism line; they’ve been described as one of the most efficient in the market. It has a team of dedicated in-house professionals that work to carefully craft products that are as modern as they are effective and innovative. Its selection started with piano lamps and picture lights, but has grown to include other lighting solutions, home goods, and sports gear.

The Cocoweb ARMBAR Heavy Duty Bicycle U-Lock has received a lot of positive reviews and we dare to say that with its features, it has earned them. The ArmBar was designed to last as it sports a 0.55-inch-thick alloy steel bar that’s been heated for extra strength and resistance to cutting. It comes with an anti-theft locking mechanism which integrates a disc cylinder system that uses flat keys—it comes with 2 keys.

It includes a robust and sturdy mount made with heavy-duty plastic and coated with PVC, which the body of the ArmBar U-lock has as well. The coating protects the paintwork on your bike from damage that scratches would have inflicted on it. The mount is easily installed and holds the U-lock firmly while you ride, without any clanging noise interrupting your peace. On the keyhole, there’s a dust cover that can be slid over and away from the keyhole; this protects the keyhole from the elements and lessens the chances of the locking mechanism becoming stiff.

Here’s another U-lock from Cocoweb:
  • The Heavy Duty Bike U-Lock and Security Cable has long-lasting 0.45-inch heated alloy steel, weather guard, and protective PVC coating.
The ArmBar is protected by a 1-year warranty, and you’re advised to keep the tags on keys for identification in case they’re stolen or lost.

How Do I Choose the Best U Lock?

Bike locks come in different forms and styles. There are about three main types of bike locks for bike cruisers – the chain lock, the cable lock, and the U-lock. They all have their various strengths and advantages that make them suitable for use in different situations. For instance, because of their longer lengths and flexibility, you’d want to use a chain lock or cable lock to securely lock your bike to a signpost or bike rack if you’re going to leave it for an extended period of time. But if you’re looking for a quick, convenient locking mechanism to take care of your bike when you’re making a quick stopover, then you should be thinking about U-locks.

A good U-lock makes the huge difference between finding your bike safe where you left it and having to get a replacement. A U-lock is a simple and functional device that’s specifically designed to secure bikes. It gives the best balance between practicality, security, and price, as far as bike locking systems go.

It comprises of two separate parts—a long U-shaped shackle and the corresponding straight crossbar with holes that fit into the ends of the U-shape to form a D-shaped lock. In other words, you can describe it as an extremely long padlock that goes between your bike’s frame and back wheel to lock and keep it safe; it can also be key or combination-locked.

Its simplicity belies its great strength and toughness, which makes it quite difficult for bike thieves to break apart using bolt cutters. For the heavy-duty U-locks, only a powerful angle grinder can crop it, which is an impracticality for most thieves.

There are a few things you should know and keep in mind so you can make the best selection of a truly secure U-lock device. They include the lock type, construction material, size, security rating, portability, cost, and any other extra feature that makes for greater performance. These features are discussed at length in this buying guide, so keep reading.
Product prices are affected by a number of factors, the most obvious being the features and design of the product in question. A feature-packed product will cost more than its counterpart with lesser features. To make the right selection at the best price point, you need to identify the feature you most need in a product and then search for the item that has it at the price convenient for your budget.

The U-locks featured in our review range from approximately $25 to $83 which encompasses both high-end and low-end U-locks for your budget comfort. Whichever product you pick from our product review section, be assured that you’re dealing with only the best from reputable manufacturers.

Of course, there are numerous cheap U-locks out there. We came across them, but owing to their flimsy makeup, we ignored them because we wouldn’t want you spending money for a bike replacement because the U-lock you bought couldn’t even secure a stick if its life depended on it.
There are important factors and features to look out for when shopping for the U-lock that will secure your bike at all times. These features include:
  • Construction material
  • Lock type
  • Security rating
  • Size
  • Portability
  • Extra features
Construction and Design
The best U-locks are made of hardened steel. Steel is an extremely hard metal to cut on a good day, and when it passes through a special hardening process, it becomes practically impossible to cut through unless you employ the use of power tools—which is just too much stress for the common bike thief. There are other metals that can be used in manufacturing U-locks such as iron and aluminum, but they don’t offer the same level of hardness as steel. You should also note that steel U-locks are more expensive than U-locks made from other metals, so you have to think about how safe you really want your bike to be against what you’re willing or able to pay for the security.

Lock type refers to the type of locking mechanism built into the U-lock. Different brands equip their U-locks with either a key lock or combination lock. Both offer the same level of security, but the combination lock has the advantage of your not having to worry about losing or forgetting your key. So, choosing a U-lock with either a key lock or combination lock is based on individual preference (and on whether you’re good at not losing or misplacing items like keys).

There are different sizes of U-locks as well. The size here refers to the diameter of the U-shaped shackle. The larger the diameter, the harder it is to cut with a bolt cutter, which most thieves employ in stealing things like secured bikes. The U-locks with diameters below 13 millimeters (<0.5 inches) will be prone to attack from medium bolt cutters, a tool which most bike thieves have, while a U-lock with a diameter from 13 to 15 millimeters (0.5 to 0.6 inches) will be much more difficult to cut. Leading the range are U-locks with 16 to 18-millimeter (0.63 to 0.71-inch) diameters that cannot be cut with even large-sized bolt cutters.

At this point, it’s fair to point out that the larger the thickness of a U-lock, the heavier it is and the more difficult it’ll be to move around with. For convenience, it’s recommended you go for mid-sized U-locks so it won’t be cumbersome to move around, unless you live or work in areas with a high theft rate. In that case, you’ll be better off with the large-sized U-locks if you can find a way to deal with the weight.
Performance and Ease of Use
U-locks are built to be portable, but this depends solely on the diameter of the U-lock. Generally, the smaller the diameter, the lighter and more portable it is. Although when compared with other bike locks such as the chain lock and cable lock, even the heaviest U-lock tends to be lighter than them on average.

U-locks are also easy to use; in fact, they’re as easy as using a padlock. All you need to do is hold the frame and back wheel of your bike together with the U-shaped shackle, fix the ends into their slots on the straight crossbar, and turn the key or set the combination. It doesn’t even take a minute to secure your bike with it, and there’s absolutely no pre-assembly required.

To check the security rating of the U-lock you want to buy, it’s highly recommended that you check the Sold Secure Rating for that particular U-lock. Sold Secure developed a three-tier grading system that grades bike locks according to their security level. A gold rating means the product offers the highest possible security for your bike, a silver rating indicates that the product offers some level of security at an affordable cost, while a bronze-rated lock offers the most basic protection against an opportunistic thief.

Checking your preferred U-lock with the Sold Secure will give you a broader idea as to the security level that will be availed your bike if you purchase it.

Another important feature that affects the performance of the U-lock is the space between the U-lock arms. The smaller the space, the better. A U-lock with small space in between is infinitely more difficult to cut, as the U-lock will give less room for maneuvering a bolt cutter to successfully cut through the lock.

For easy and better storage and transportation, some U-locks come with a frame mount that allows you to carry it on the frame of your bike. This feature saves you the stress of trying to fit the U-lock into your bag, especially given its odd shape that makes it a little awkward to transport in the bag.

Get the Best U Lock of 2023!

Thank you for reading this review to the end. By now we’re sure that you must have seen a U-lock from our listed products that fits your requirements. You can now go ahead and make a well-informed purchase.

Our Top Choice
OnGuard Bulldog DT
Best Value
Sigtuna Gear 16mm Bike Lock + Cable Combo
Kryptonite New York Fahgettaboudit Mini
ABUS Yellow Mini 40 U-Lock
Cocoweb ARMBAR Heavy Duty U-Lock