The fastest way depends on what kind of lock you have
If you have lost the key to a file cabinet, you have three practical routes: picking the lock yourself, calling a locksmith, or forcing the cabinet open. Which one makes sense depends on whether you own the cabinet, whether you need to preserve it, and how much time you have. A locksmith will open it reliably but costs money. Picking works on many cheaper cabinets but requires tools and patience. Forcing it open is fastest but will damage the cabinet.
Before you start, confirm you actually own the cabinet or have permission from the owner to open it. If this is a cabinet at work, check with your manager or facilities team first — they may have a master key or know where the original key is stored.
Key Takeaways
- Locksmiths can open most file cabinets in under an hour and cost between $50 and $150 depending on lock type and your location.
- Picking a pin-tumbler lock (the most common type on office cabinets) requires a tension wrench and pick, both available in lock pick sets under $20.
- Forcing the cabinet open with a pry bar or screwdriver will damage the lock and frame but takes only a few minutes.
- Lateral file cabinets with cam locks are easier to pick than vertical cabinets with pin-tumbler locks.
Calling a locksmith is the safest option
A locksmith can open almost any file cabinet lock without damaging it. They carry specialized tools and know how to work with different lock types — pin-tumbler locks, cam locks, and tubular locks all require different techniques. Most locksmiths can arrive within a few hours and finish the job in 15 to 30 minutes.
Cost varies by location and lock complexity. A simple cam lock on a lateral cabinet typically costs $50 to $75. A pin-tumbler lock on a vertical cabinet may run $75 to $150. Call ahead and describe the cabinet type and lock to get an estimate. Ask whether they charge a service call fee separate from the opening fee, and whether they can rekey the lock so you can use a new key instead of replacing the whole lock.
This is the best choice if the cabinet belongs to your employer, if you need the cabinet to remain undamaged, or if you are not comfortable attempting the other methods.
Picking a pin-tumbler lock with basic tools
Most vertical file cabinets use a pin-tumbler lock, the same mechanism found in house door locks. You can pick one with two tools: a tension wrench (a small L-shaped piece of metal that applies rotational pressure) and a pick (a thin tool that manipulates the pins inside). Both come together in lock pick sets sold online for $10 to $25.
Insert the tension wrench into the bottom of the keyhole and apply gentle rotational pressure — the direction depends on the lock, so try both ways. While holding that pressure, insert the pick into the top of the keyhole and feel for the pins inside. Push each pin upward until you feel it catch. When all pins are set, the lock should turn. This process takes anywhere from a few minutes to an hour depending on your feel for the mechanism.
If the lock has a security pin (a pin with a ridge or shoulder), picking becomes much harder and may not be possible without professional tools. If you feel resistance that does not change after several minutes, the lock likely has security pins and a locksmith is your better option.
Picking a cam lock on lateral cabinets
Lateral file cabinets often use a cam lock, a simpler mechanism than a pin-tumbler. A cam lock has a rotating metal piece (the cam) behind the keyhole that moves a bolt in and out. These are much easier to pick because you only need to manipulate one moving part instead of five or six pins.
You can sometimes open a cam lock with just a tension wrench and a flat pick. Insert the tension wrench and apply light rotational pressure. Insert the flat pick and feel for the cam — it usually sits at the bottom of the keyhole. Push it upward or sideways (depending on the lock design) until it catches and the bolt retracts. Cam locks often open in under a minute once you find the right angle.
If the cabinet has a tubular lock (a round keyhole rather than a traditional slot), picking is much harder and usually requires a specialized tubular pick tool. A locksmith is the practical choice for tubular locks.
Forcing the cabinet open if time is critical
If you need the cabinet open immediately and do not care about preserving it, you can pry it open with a flathead screwdriver or pry bar. This will damage the lock and likely the frame around it, but it takes only a few minutes.
Insert the screwdriver or pry bar into the gap between the drawer and the cabinet frame, near the lock. Apply steady pressure to bend the frame or break the lock mechanism. You may need to work along the edge of the drawer to spread the force. Once the frame bends enough, the drawer will slide open.
This method is practical only if you own the cabinet outright and do not plan to use it again, or if you are willing to pay for repairs afterward. If the cabinet is valuable or belongs to your employer, this will likely cost more in repairs than a locksmith would charge.
What to do after you open the cabinet
Once the cabinet is open, you have two choices for the lock: replace it or rekey it. Replacing the entire lock mechanism costs $30 to $80 in parts plus locksmith labor if you want professional installation. Rekeying means the locksmith disassembles the lock and rearranges the pins so a new key works — this usually costs $40 to $100 and preserves the original lock.
If you forced the cabinet open and damaged the lock, replacement is your only option. If a locksmith picked it, ask them to rekey it at the same time — it is faster and cheaper than doing it separately later. Keep the new key in a safe place, and consider leaving a spare with a trusted colleague or in your office safe.
Frequently Asked Questions
Can I pick a file cabinet lock if I have never done it before?
Yes, if it is a cam lock or a simple pin-tumbler without security pins. Cam locks often open in minutes with basic tools. Pin-tumbler locks take longer and require developing a feel for the mechanism, but many people succeed on their first try. Tubular and high-security locks are much harder and usually require a locksmith.
Will picking the lock damage it?
Not if you do it carefully. Picking applies only rotational pressure and does not bend or break anything. The lock will still work normally once it is open. Forcing the cabinet with a pry bar, by contrast, will almost always damage the lock and frame.
How much does a locksmith cost for a file cabinet?
Most locksmiths charge $50 to $150 depending on lock type, location, and whether they rekey the lock. Call for an estimate before they arrive. Some charge a service call fee ($25 to $50) on top of the opening fee, so ask about the total cost upfront.
What if the cabinet is at my workplace?
Check with your manager or facilities team first. They may have a master key, know where the original key is stored, or have a preferred locksmith on contract. If the cabinet belongs to the company, you should not pick or force it open without permission.
Can I use a bump key on a file cabinet lock?
Bump keys work on some pin-tumbler locks but not reliably on file cabinet locks, which often have security pins or tighter tolerances. A standard lock pick set is more likely to work. If bump keys do not open it in a few tries, switch to traditional picking or call a locksmith.