Does pick resistance matter for a storage unit lock?

Barely. Picking is slow, requires practice and leaves the attacker standing at the door. Storage unit theft is overwhelmingly cutting, so shackle protection matters far more than cylinder quality, which is the opposite of how padlocks are usually marketed.

Should I use a keyed or combination lock on a storage unit?

Combination suits infrequent visits where losing a key is the realistic failure. Keyed suits shared access, because a shared combination cannot be revoked. A rekeyable keyed lock such as the American Lock A2010 allows access to be revoked without buying new hardware.

Is a more expensive storage padlock worth it?

Up to roughly thirty-five dollars, yes, because that is the range where a lock moves from an exposed shackle to a shrouded or disc body and changes the outcome of the only attack that matters. Beyond that the money is often better spent checking the facility's own latch and hasp.

Will a storage unit padlock survive outdoors all year?

Stainless with a covered keyway will. Zinc-plated steel lasts a few years. Laminated bodies are the worst choice because water sits between the plates. In open-air corridors with freeze-thaw cycles the keyway cover matters as much as the body material.

Guide Padlocks Updated 2026

Best Padlocks for Storage Units (2026.)

Q: What kind of lock do storage units require?

Many facilities require a disc-style lock because the latch is built to accept and shield one, and some refuse standard padlocks outright. Others sell an approved lock at the desk. Calling to ask before ordering avoids the most common reason a storage lock is returned.

Q: Are disc padlocks really bolt cutter proof?

Not proof, but close in practice. Cutters must close their jaws around the shackle and a disc body leaves almost none of it reachable. A quality disc lock moves the attack from bolt cutters to an angle grinder, which is louder, slower and far more conspicuous.

Don't let a $5 lock guard your $5,000 of stuff. Storage units have the narrowest threat model in this whole category — nobody is picking your lock, they are cutting it — which makes the buying decision unusually simple and unusually easy to get wrong.

By Johnny T. · March 2026 · 11 min read

Some links on this page are affiliate links — we may earn a commission.

Storage unit theft is one of those crimes that feels invisible until it happens to you. No broken window, no kicked-in door — just a cut padlock and a cleaned-out unit.

Most facilities hand you the keys and tell you to bring your own lock. Most people grab whatever's cheapest at the hardware store. That's the mistake, and the gap between a lock that resists bolt cutters and one that doesn't is usually fifteen to thirty dollars.

How to read this guide

We do not own these locks. Recommendations are built from specification, mechanism and consensus, and tagged accordingly.

TestedPhysically in hand. Nothing on this page carries this tag.

DocumentedPublished specification or primary source.

ManufacturerThe maker's own claim. A claim, not a fact.

CommunityLocksmith and locksport consensus. Informed opinion.

The whole guide in one line Nobody picks a storage unit lock. They cut it. Buy shackle geometry, not pin count.

Chapter 1

What Makes A Good Storage Lock

A threat model narrow enough to actually optimise for

Most security advice has to hedge because the threat could be anything. Storage units are the exception. The attack is bolt cutters, with angle grinders on higher-value targets, and almost nothing else. Community

That narrows the buying decision to three things:

Shackle protection above all. Either a shrouded body, a disc design that leaves almost no shackle exposed, or a shackle hard and thick enough to stop 36-inch cutters. As we argue throughout the site, cut resistance is a matter of geometry before hardness — jaws that can't close on a shackle can't cut it, whatever it's made of.
Weather. Storage corridors are frequently open-air. Your lock sits through rain, freeze-thaw and humidity all year. Corrosion-resistant materials and a sealed or covered keyway aren't luxuries here.
Pick resistance barely matters. It's the thing every lock is marketed on and the thing least relevant to this specific door. A five-pin cylinder is fine. Spend the money on the body.

Check the facility's rules before you buy

Worth doing first, because it can decide the whole purchase. Many facilities require a disc-style lock, because their latch is built to accept one and to shield it — and some will refuse a standard padlock outright. Others sell an approved lock at the desk. Five minutes on the phone before ordering saves a return.

The lock is probably not the weakest part

This is the argument we make about door frames and about shed hasps, and it applies here too. A roll-up door's latch, the hasp welded to it, and the door's own bottom rail are all part of the system, and none of them are things you chose. A hundred-dollar lock on a latch that can be levered off is a hundred dollars spent on the wrong component.

Look at what your lock actually attaches to before you decide how much lock to buy. If the hasp is thin or the fixings are exposed, tell the facility — it's their hardware, and it's their problem to fix.

Chapter 2

Our Picks

Five locks, in order of who should buy them

Best Overall

ABUS Diskus 20/70

~$35 – $50

Best overall

The Diskus design is the standard for storage units and ABUS makes the original. The circular stainless body wraps almost entirely around the shackle, leaving a sliver of hardened steel exposed — the opening is 17 mm vertical by 20 mm horizontal. Documented Bolt cutters have nowhere to sit. Defeating it means an angle grinder, and the curved body makes even that awkward.

The cylinder is an ABUS Plus disc detainer — not a pin tumbler at all, but a stack of rotating discs, so conventional picks, raking and bumping simply don't apply. Documented Stainless inside and out with a covered keyway, which is what you want in an open-air corridor.

Measure the facility's latch first. That 17 mm opening is smaller than a cheap brass padlock's, and the 10 mm shackle is fat. Storage hasps are usually designed for exactly this lock — but confirm before ordering.

Check price on Amazon

Best Budget

Master Lock M40XD Magnum

~$18 – $25

Best budget

Master Lock takes a lot of deserved criticism on this site — see the 140D and the No. 3 — but the Magnum line is a genuine step up from their consumer padlocks, and the difference is exactly the thing that matters here.

The M40XD has a shrouded shackle: the hardened steel body extends up around the shackle on both sides, so getting cutter jaws around it is very difficult. Not as elegant as the Diskus, same objective, roughly half the price.

The keyway is a standard pin tumbler and nothing special. In any other context we'd mark that down hard. Here it's close to irrelevant — nobody is picking your storage lock.

Check price on Amazon

Premium Pick

American Lock A2010 (Rekeyable)

~$30 – $45

Premium

If you want a traditional padlock shape with serious cut resistance, this is where to look. The 7/16″ boron alloy shackle is among the hardest materials used in commercial padlocks and it will eat bolt cutter blades. Solid steel body, zinc-plated for weather. Manufacturer

The six-pin rekeyable cylinder is the real argument for it over the Diskus: you can change the key yourself if you've handed out access and need to revoke it. The Diskus can't be rekeyed at all. If a business shares a unit, that's a meaningful difference. Same logic as the ABUS 83/55 Rock, in a cut-resistant body.

Its one weakness is honest: the shackle is exposed. Boron is hard, but geometry beats hardness, and an angle grinder gets to it. For opportunists with cutters it's more than enough.

Check price on Amazon

Best Combination Option

ABUS Diskus with Combination

~$25 – $35

No keys to lose

Losing the key to a storage unit is its own special misery. The combination Diskus gives you the same shrouded disc body and the same immunity to cutters, with a four-digit resettable combination instead of a cylinder.

You give up pick resistance, which in this context costs you almost nothing. The combination mechanism is decent — tolerances tight enough that decoding by feel would take real effort and knowledge, unlike the grocery-aisle dial locks in our budget roundup, which are decoded by counting. Community

For a unit you visit twice a year, this is genuinely the convenient choice without a meaningful security trade.

Check price on Amazon

Honorable Mention

Stanley Hardware CD8820

~$12 – $20

Good enough

If the ABUS is out of budget, the CD8820 offers the same disc form factor for less. It isn't as refined — cheaper cylinder, not stainless, looser shackle tolerances — but the fundamental design advantage still applies. Cutters can't get a grip on a disc.

Think of it as the "good enough" option. It won't impress anyone in locksport, but it stops the attack that actually happens. If your alternative is a seven-dollar Master Lock No. 3, this is an enormous upgrade for very little money.

Check price on Amazon

Chapter 3

What To Avoid

Including one category that looks right and isn't

Anything with a thin, exposed laminated or brass shackle. Any combination lock from a checkout aisle. Anything marketed as "luggage" or "locker" grade.

Master Lock No. 1, No. 3 and No. 5 are the specific offenders, because they're the ones people actually buy. All three can be cut in seconds with basic bolt cutters, and laminated padlocks of this type are the classic target for shimming — a strip cut from a drinks can, worked down the shackle, retracts the latch without any key at all. Community They have no business on a storage unit door.

Worth noting what the No. 3 actually is, since we've measured it: a genuinely tough laminated body with a 9/32″ shackle — thicker than an ABUS 55/40's — wrapped around a four-pin cylinder that opens to a rake in about a second. Good metal, wrong lock.

"It's disc-shaped, so it's a disc lock."

Be careful with no-name disc padlocks on marketplaces. The shape alone isn't magic. Cheap versions use soft steel that a grinder goes through quickly, the housings are pressed or screwed rather than welded so the halves can be split, and the cylinders can be crude enough to yield to a tension wrench and improvised pick. The shape buys time; material quality and construction decide how much. Community

VerdictJudge a disc lock on what's inside the disc, and on how the halves are joined.

Why nobody can tell you how often this happens

Every page on this subject, including the previous version of this one, quotes a break-in figure attributed to unnamed industry estimates. We went looking for the primary source and found something more useful than the number: a structural reason the number doesn't exist.

The FBI's Uniform Crime Reporting handbook contains what's known as the "hotel rule." Where a number of dwelling units under a single manager are burglarised, and the offences are most likely to be reported to police by that manager rather than by the individual tenants, the whole event is scored as one offence. Documented

As a retired police officer put it in a self-storage industry interview: if a burglar hits twenty units at one location and the manager calls the police, the number of burglaries recorded is one.

What that means for you

Storage unit burglary is systematically undercounted in the only national dataset that exists — not through anyone's dishonesty, but because the reporting rule was written for hotels and self-storage inherited it. Any confident national figure you read is either an extrapolation or an invention.

The one properly attributed figure we could find is old but real: the 2013 Self-Storage Almanac reported that 8.9% of surveyed facilities had experienced a break-in or theft during 2012. Documented Facility-level, not unit-level, and more than a decade out of date — but it is sourced, which is more than the numbers it competes with.

The attack your lock doesn't stop

Worth knowing before you spend fifty dollars on a padlock. A recurring pattern reported across the industry is that a thief rents a unit legitimately, then goes through the partition wall or over the top into the units either side — sometimes clearing an entire row without touching a single lock. Community

Nothing you hang on your door addresses that. What does: choosing a facility with interior climate-controlled units rather than drive-up doors, individual unit alarms, and access logging that ties entry to a specific tenant. When you're comparing facilities, those are worth more than the lock you bring — and it's the one part of this decision you make before you sign, not after.

Questions

The Ones People Actually Ask

Short answers

What kind of lock do storage units require?

Many facilities require a disc-style lock, because the latch is built to accept and shield one, and some refuse standard padlocks entirely. Others sell an approved lock at the desk. Call and ask before ordering — it's the single most common reason a storage lock gets returned.

Are disc padlocks really bolt cutter proof?

Not proof, but close in practice. Cutters have to close their jaws around the shackle, and a disc body leaves almost none of it reachable. A quality disc lock moves the attack from cutters to an angle grinder, which is louder, slower and far more conspicuous in a storage corridor.

Does pick resistance matter for a storage unit?

Barely. Picking is slow, needs practice and leaves the attacker standing at the door. Storage unit theft is overwhelmingly cutting. Buy shackle protection and treat the cylinder as a secondary consideration — the opposite of how most padlocks are marketed.

Should I get a keyed or combination lock?

Combination, if you visit rarely and losing a key is your realistic failure mode — the combination Diskus gives up almost nothing that matters here. Keyed, if several people need access, since a shared combination can't be revoked. A rekeyable keyed lock like the American Lock A2010 lets you revoke access without buying new hardware.

Is a more expensive lock actually worth it?

Up to about thirty-five dollars, yes — that's the range where you move from an exposed shackle to a shrouded or disc body, which changes the outcome of the only attack that matters. Past that you're buying refinement, and the money is often better spent checking that the facility's own latch and hasp aren't the weak point.

Will my lock survive outdoors all year?

Stainless with a covered keyway will. Zinc-plated steel is fine for a few years. Laminated bodies are the worst option, because water sits between the plates. In an open-air corridor with freeze-thaw cycles, the keyway cover matters as much as the body material.

The Bottom Line

Buy The Shape, Then Check The Latch

For most people the ABUS Diskus 20/70 is the right answer — the sweet spot of cut resistance, weather durability and price. If budget is tight, the Master Lock M40XD Magnum gives you most of the protection for about half. If several people need access and you may have to revoke it, the American Lock A2010 and its rekeyable cylinder is worth the exposed shackle.

Whichever you pick, you're doing better than most of the units on your corridor — and on a row of identical doors, being the harder target is most of the job.

The short answer

Diskus 20/70 if you can, Magnum if you can't, and five minutes checking what the lock actually hangs on before either.

Sources & Method

ABUS Diskus 20/70 specification — Documented Stainless body and hand-welded seam, 10 mm shackle, 17 mm vertical and 20 mm horizontal clearance, ABUS Plus disc detainer cylinder, not rekeyable. Full detail in our review. ABUS product data
Master Lock No. 3 construction — Documented 1-9/16″ laminated steel body, 9/32″ hardened shackle, non-rekeyable four-pin W1 cylinder. Cited here because the body is better than its reputation and the cylinder is worse. Head-to-head.
Shackle protection and cut resistance — Community Consensus that shackle exposure determines cut resistance more than shackle diameter, which is why shrouded and disc bodies outperform thicker exposed shackles. Applied consistently across our padlock coverage.
Shimming laminated padlocks — Community A long-documented bypass on laminated padlocks of this type using a thin metal shim. Background in our shimming write-up. We have not performed it on these specific models.
Why storage burglary figures are unreliable — the UCR "hotel rule" — Documented The FBI Uniform Crime Reporting handbook scores the burglary of multiple dwelling units under one manager as a single offence where the manager, rather than individual tenants, reports it. Self-storage falls under this rule, so multi-unit break-ins are recorded as one incident. Explained by Justin Insalaco, retired police officer and strategic advisor, in industry coverage of self-storage theft. Modern Storage Media
Facility-level break-in rate — Documented 2013 Self-Storage Almanac: 8.9% of surveyed facilities reported a break-in or theft during 2012. Facility-level rather than unit-level, and over a decade old — cited because it is attributable, unlike the figures usually quoted. Reported here
Correction — "industry estimates" on annual claims — Corrected An earlier version of this page cited unnamed industry estimates for annual storage break-in claims. We could not trace that figure and have replaced it with the sourced material above, plus an explanation of why a reliable national figure does not exist.
Rented-unit and wall-breach burglaries — Community Widely reported by operators and security vendors: a thief rents a unit, then breaches the partition wall or goes over the top into neighbouring units. Reported as an industry pattern rather than a quantified rate.
Materials and shackle specifications for the other picks — Manufacturer Boron alloy shackle, shrouded body designs, plating and cylinder types as published by American Lock, Master Lock and Stanley. Manufacturer claims, reported as such.
Facility lock requirements — Community Requirements vary by operator and by site. Widely reported that many facilities specify disc locks; we have not surveyed operators, so treat it as a prompt to phone yours rather than a rule.

This is a researched guide — we do not own these locks and nothing here is tagged as hands-on. If you've had a lock cut off a unit, or one survive an attempt, that's the most useful data there is: send it over and you'll be credited.