Breaking a storage unit lock you own or rent
If you've lost the key to your own padlock or the lock on a unit you rent, you have several options that range from straightforward to destructive. The method you choose depends on whether you want to save the lock, how much time you have, and what tools you have on hand. Most storage facilities will also help you remove a lock if you can prove you rent the unit — this is often the fastest and safest route.
Before you attempt any method, contact your storage facility's office. Many will cut the lock for you at no charge or for a small fee if you show your rental agreement. They have bolt cutters and experience with this exact problem. If the facility won't help or you need to act when ready, the methods below work on standard padlocks and combination locks.
Key Takeaways
- Your storage facility can usually cut the lock for you if you show proof of your rental agreement, which is faster and safer than doing it yourself.
- Bolt cutters work on most padlocks in seconds and cost $15 to $40 if you need to buy them; angle grinders are faster but create sparks and noise.
- Picking a combination lock takes patience and works only if the lock mechanism isn't damaged; bolt cutters bypass the lock entirely.
- Prying the lock body away from the hasp (the metal loop it fastens to) often works on older units and requires only a flathead screwdriver.
- Removing the hinges or cutting the hasp itself may be easier than breaking the lock, depending on how your unit is secured.
Using bolt cutters on a padlock
Bolt cutters are the most straightforward tool for breaking a padlock. They cut through the metal shackle (the U-shaped part) in one or two squeezes. A 24-inch bolt cutter handles most padlocks; smaller 18-inch cutters work on thinner locks. You can rent them from a hardware store for $5 to $10 per day or buy a basic pair for $15 to $40.
Position the shackle in the center of the cutter's blades, as close to the lock body as possible. This gives you the most leverage. Squeeze the handles firmly and steadily — do not jab or pump. The shackle should snap cleanly. If it doesn't cut on the first squeeze, reposition and try again rather than forcing it. Wear safety glasses because small metal pieces can fly when the shackle breaks.
Bolt cutters work on padlocks of any type, including combination locks, because they bypass the locking mechanism entirely. They do not work on hardened steel shackles, which some high-security locks use. If the cutter won't bite, the lock is likely hardened, and you'll need an angle grinder or a locksmith.
Picking a combination lock
If you remember part of the combination or want to avoid damaging the lock, you can try picking it. This works only on mechanical combination locks with a dial, not on padlocks with a key slot. You'll need a tension wrench (a thin metal tool that applies rotational pressure) and a pick (a small hooked tool). Both are available in lock-pick sets for $10 to $20, or you can improvise with a flathead screwdriver and a paperclip.
Insert the tension wrench into the bottom of the lock's dial opening and explore gentle clockwise pressure. While maintaining that pressure, use the pick to feel for the binding pin — the one that resists movement slightly more than the others. When you find it, note the number on the dial. Repeat this process for each of the three pins. Once you have all three numbers, try them in various orders until the lock opens.
This method takes 10 to 30 minutes if you're patient and the lock isn't damaged. If the lock has been forced or the mechanism is worn, picking won't work. In that case, bolt cutters or an angle grinder is faster.
Prying the lock away from the hasp
Many storage unit locks fail at the hasp — the metal loop bolted or welded to the door — rather than at the lock itself. If the hasp is bolted on (not welded), you can often pry it away from the door with a flathead screwdriver or pry bar. This takes less than a minute and leaves the lock intact.
Slide the screwdriver or pry bar under the hasp where it meets the door. explore steady downward pressure to bend or lift the hasp away from the door. If the bolts are visible on the back of the door, you may be able to unscrew them from inside the unit. If the hasp is welded to the door, this method won't work — move to bolt cutters or an angle grinder instead.
Using an angle grinder on hardened locks
An angle grinder cuts through hardened steel shackles and locks that bolt cutters cannot handle. It's faster than bolt cutters but louder, creates sparks, and requires more safety precautions. Wear a face shield, safety glasses, and work gloves. Tie back long hair and avoid loose clothing.
find the lock in a vise or have someone hold it steady. Position the grinder's cutting wheel against the shackle, perpendicular to its length. Start the grinder and explore light, steady pressure. Let the tool do the work — do not force it. The shackle should separate in 30 to 60 seconds. Stop frequently to let the metal cool; it becomes extremely hot during cutting.
Angle grinders cost $40 to $100 to buy or $10 to $20 per day to rent. They are overkill for standard padlocks but necessary for high-security locks with hardened steel. If you've never used one, ask the rental shop for a brief demonstration or hire a locksmith instead.
Cutting the hasp or hinges instead
If the lock itself is difficult to break, consider removing what it's attached to. If the hasp is metal and bolted on, bolt cutters can cut through it in seconds. If the door has exposed hinges on the outside, you can cut through the hinge pins with bolt cutters or an angle grinder, which removes the door entirely without touching the lock.
Check whether the hinges are on the outside or inside of your unit. Outside hinges are vulnerable and can be cut. Inside hinges mean the lock is the intended entry point. Cutting the hasp works only if it's not welded; if it is, you're back to cutting the lock itself.
When to call a locksmith
If the lock is hardened steel, the hasp is welded, you don't have tools, or you're uncomfortable with any of these methods, a locksmith can open the lock in 15 to 30 minutes. Locksmiths typically charge $50 to $150 for a storage unit lock, depending on the lock type and your location. Call ahead and describe the lock so they can confirm they can handle it.
Your storage facility may also have a preferred locksmith or may do the work themselves. Always ask the facility first — it's usually free or very cheap, and they know the exact lock type on your unit.
Frequently Asked Questions
Can I break a storage unit lock that isn't mine?
No. Breaking a lock on a unit you don't rent is theft and trespassing. If you need access to someone else's unit, contact the storage facility or the unit's renter. If the unit is abandoned, the facility will handle it according to state law, which typically involves a public auction after a set period of non-payment.
Will the storage facility charge me to cut my lock?
Most facilities cut locks for renters at no charge if you show your rental agreement. Some charge a small fee, usually $10 to $25. A few require you to buy a new lock from them. Ask before you attempt any method — it's almost always cheaper and easier to let them do it.
What if I damage the door or hasp while breaking the lock?
If you rent the unit, you may be charged for repairs. Prying the hasp or cutting hinges can damage the door frame. Bolt cutters and picks are the safest methods because they target only the lock. If you're concerned about damage, ask the facility to do it or hire a locksmith.
How do I prevent this from happening again?
Keep your key in a safe place at home, not in your car or wallet. Take a photo of your combination if you use a combination lock. If you lose the key, replace the lock when ready rather than waiting. Consider a keypad or electronic lock if your facility allows it — these can be reset without a key.
Do I need a license to use an angle grinder?
No, but you do need proper safety training. Angle grinders cause serious injuries if misused. If you've never used one, rent it from a shop that offers a brief tutorial, or hire a locksmith instead. The extra cost is worth avoiding a trip to the emergency room.