Whether you’re in the early planning stages of your move or you want to store some holiday decorations, you need a strong lock for your storage unit  There are three basic types of storage unit locks, with most ranging from about $10–$400. Move.org put together some tips and tricks to help you choose the best lock for your self-storage unit:

1. Disc locks are the most popular for self-storage protection.
2. Find a closed shackle or shrouded shackle lock.
3. Stay away from the cheapest option.

• Why you need a lock
• Types of locks
• Best metal for my storage lock
• Our top lock recommendations
• Tips and tricks
• FAQ
• Recommended resources

Whatever company you choose for self-storage, you need a lock for your unit. Some places have locks on-site you can buy, but you often need to purchase one ahead of time. Visit a home improvement store in your area, or check online for a wider variety of options.

Some storage companies offer more robust security to help put your mind at ease, but that doesn’t mean you should leave your unit open. Security-minded companies like Life Storage advertise keypad access, video surveillance, and security guards on the premises, all of which make it difficult for thieves to even make it to your storage unit door. But if all else fails, or if you use a company without these security features, a good storage lock is your last line of defense against theft and an absolute necessity for self-storage. The next step is deciding which type of lock works best for you.

Storage unit locks vary by design, size, quality, and cost. There are hundreds to choose from, and prices range from about $5 to $5,000 (seriously). Don’t worry, you don’t need to take out a loan for a storage lock. Most people should expect to pay anywhere from $30-$150. A cheaper lock could be risky, and more expensive ones are impractical for everyday storage needs.

Closed-shackle padlocks are like an upgraded version of the combination lock you probably used on your junior high gym locker.

Standard padlocks are easy for thieves to slice through with bolt cutters. That’s why you want a closed-shackle padlock where the U-shaped bar at the top (the “shackle”) is thicker and less visible than a regular padlock. Because the shackle isn’t exposed, there’s no room for a looter to snip through the lock and run off with your stuff.

Expect to pay anywhere from $30 to $130 for a quality closed-shackle padlock.

Cylinder locks offer some of the best security. They’re what you have on your front door. The “lock” part is inside the door, so thieves either need your key—or they have to pick the lock or break the door down.

A cylinder lock, or pin tumbler lock, uses various lengths of pins that move in a pattern when the correct key is inserted into it.

These locks are great in theory but tricky to use in real life. Not all storage units allow cylinder locks, and those that do often have strict size requirements. Cylinder locks are also a pain to install and repair (think lots of power tools). So while they offer the best protection, they usually aren’t a realistic option.

A decent-quality cylinder lock generally costs between $45–$170.

Disc locks are the most popular type of storage unit protection. These locks are basically the same thing as closed-shackle padlocks—their construction allows for the shackle to be mostly hidden when in use.

Disc locks are easy to use, and the circular shape and small opening makes the locks a nightmare for crooks to tamper with. The combination of usability and security makes this lock a favorite of both storage unit customers and self-storage companies.

Costs range from about $30–$120 depending on how strong you want your lock (read more below).

When you’re done choosing between three types of locks, you’ll narrow down the metal that best fits your needs. Some companies swear by certain metals, and competitors use something else entirely. It can be nerve-wracking to compare alloys, but luckily, there are some key points that will help you narrow down the list.

When you use an outdoor storage unit, there are a few things you need to keep in mind. Your lock is going to be exposed to heat, cold, and moisture that you wouldn’t see indoors.  If your storage unit is outdoors, rain and snow can gradually weaken the metal on your lock.

Brass is most commonly recommended for outdoor storage because it won’t rust as fast as iron or iron alloys. However, metals like brass and aluminum can still corrode over time and are softer than steel (an easier target for thieves). When you look for a outdoor storage lock, shop for an average price of around $50 and look for these selling points:

• Heavy construction
• Weatherproof coating
• Anti-drill technology
• Brass/brass alloy construction
• Shrouded/partially-shrouded shackle

When you rent an indoor storage unit, you don’t need to worry about fluctuating temperatures and moisture affecting your lock. You have only one concern: security.

Whether you choose a disc lock, cylinder lock, or padlock, you want a heavy-duty lock with fully or partially shrouded shackles. There’s plenty of discussion around the best metal for pure security, but most people agree that stainless steel is a solid contender. It’s difficult to drill or cut through, and you won’t need to worry about the rusting problem indoors.

Often, you see more expensive locks advertising rare alloys that are more difficult to cut. While it’s a good rule of thumb that more expensive locks provide more security, you don’t need to worry if you can't pay $150+ for a lock. You can get great locks in the $40–$60 range, but be sure to look for these key features:

• Heavy construction
• Anti-drill technology
• Hardened stainless steel shackle
• Shrouded shackle

There are plenty of options for you based on needs, price range, and lock strength. If you need a short list, here are our top picks for best storage locks.

• ABUS 24/70 Disc Padlock—Best overall
• ABUS 37/80 Granit Padlock—Strong
• Master Lock M50X Disc Padlock—Affordable

It can be hard to select the right lock even if you know the differences between the three main options. We’ve put together some tips and tricks that should make it easier to find an affordable, high-quality lock that’s perfect for your situation.

• Shop online. Don’t buy locks from the storage unit company or your local hardware store. Their prices are attractive, but the locks are often low-quality. Amazon has your best options.
• Go heavy. If choosing between two nearly-identical locks, go with the heavier option. It’s a sign the lock uses stronger metals.
• Use the ‘lost key’ test. When looking for a lock, ask yourself how hard it would be to break into your unit if you lost your key. If you think you could bust open the lock with a hammer or rock, chances are, a robber could too.
• Stay away from combination locks. Thinking about a combination padlock? Forget about it. These locks might be easy on your wallet, but the low quality makes them magnets for bad guys.
• Don’t be (too) cheap. Everyone likes low prices, but use some common sense and basic math. If a thief can buy bolt cutters for $30, your storage unit lock should cost at least that much. The more valuable your belongings, the more expensive your lock should be.
• Don’t jump the gun. Ask your storage unit company what size lock you need. Size requirements can vary by company, so it’s important to nail down the details before purchasing a lock.
• Think of your lock as a last line of defense. Locks are essential, but a top-notch storage facility has several extra security layers. Look for a self-storage company with gates, an electronic keypad at the entrance, and plenty of video surveillance. The best self-storage companies make it difficult for burglars to reach your storage unit.

• Best Storage Unit Locks
• Best Storage Unit Companies
• Best Climate-Controlled Self-Storage Companies
• Best Temporary Storage Solutions

• How Much Do Storage Units Cost?
• What Can (And Can’t) I Store in a Storage Unit?
• Which Storage Companies Allow 24-Hour Access?
• How Do I Estimate the Storage Unit Size I Need?