How To Open Master Lock Key Box (Without a Code)

Eli Smith
by Eli Smith
Have you lost the master code to your lock box? Don’t freak out, there’s a way you can still get it open. Luckily, you can bypass the master code in several ways if you have the serial number. It is a quick process, so follow along as we explore the steps that you can take when you forget the code for your Master Lock.

If you have lost the code to your master lock, you will probably be on the verge of tossing that lock from a window or bringing out the bolt cutters. Rather than do that, we have a guide that will help you open a master lock key box without a code. Check out our short guide below:

If it is an official Master Lock, Master Lock Company LLC allows you to submit a lost combination form. To do this, you will need to have an available serial number. Master Lock Company LLC cannot provide combinations for non-serialized locks.

Without a serial number, we will need to dig into some steps required to pick your lock. We will also go through steps to reset your combination and store it to not run into this issue again.

Related Content: How To Open A Safe Without A Key Or Code | Types of Lock Picks | Can You Damage A Lock By Picking It?

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How To Effortlessly Open A Master Lock Without The Combination – Lockpicking Steps

These lockpicking tips will assume you have access to a lockpicking kit or any standard pick. Either will work for the steps displayed below:

  • Purchase a lockpicking kit or get a pick
  • Insert the pick into the small gap next to the first number
  • Find the loose spot in the wheel
  • Repeat with the remaining numbers until the lock opens

Step One: Purchase A Pick

Step one requires you to get a lockpicking kit or a think pick. A lockpicking kit can set you back around $30 but will work for various lock situations. For most standard Master Locks, you will only need the pick for this to work.

You can use any thin sheet of metal to get this done. The only requirement is that it has to be thin enough to fit between in the gap next to your number wheel.

Step Two: Insert The Pick Into The Small Gap Next To The First Number

Take the thin sheet of metal that you have and insert it into the small gap next to the first number wheel. Keep the pick in there for the entirety of this process. Provided that you do not apply excessive force, this will not break your lock.

Step Three: Find The Loose Spot In The Wheel

Begin spinning the first number until you feel it start to get loose. As the number wheel goes to this selected number, it will be much easier to move. So there should be little to no resistance from the pick once you keep the right number.

Step Four: Repeat With The Remaining Numbers Until The Lock Opens

With the pick remaining in the same position, continue to turn the numbers until they are in a “low resistance” position. Leave these four numbers in that position, pulling open the key box on your Master Lock.

These steps assume that you have the standard “number wheel setup,” where flicking the numbers up and down is the standard model of setting your combination. These steps will not work with the push button versions. Those are also just as easy to open.

Video: Open a Master Lock with No Tools

How To Crack The Master Lock Key Box – A Step-By-Step Guide

  • Press down on the open button
  • Press down on the keys to look for those that give
  • Try out those that have movement in multiple orders

No tools are required to open this style of Master Lockbox.

Step One: Press Down On The Open Button

The simplest version of these Master Locks is all handled through notched rods. As a result, holding down the open button will cause the lock mechanism to seek out those rods. If the rods are all correct and pressed in the same order, the lock will respond by opening. In this case, you will be doing that backward.

Step Two: Press Down On The Keys To Look For Those That Give

Hold down the open button and press on each key to determine which ones give under your finger. Those that move should be mentally marked later, as they are in the four-digit code.

Step Three: Try Out The Four Buttons You Determined In The Previous Step

You will likely have to do this a couple of times to find the right order. Regardless, going from a nine to a four-button combination makes this easy. If you don’t want to go through these steps, you only have one final option.

How To Get Master Lock To Send You The Combination On A Serialized Lock

  • Fill out the lost combination form
  • Have it notarized by a notary public
  • Wait four to six weeks

Step One: Fill Out The Lost Combination Form

You can find the form on Master Lock’s website. Fill out everything entirely while leaving the section for the notary public blank. Filling out that section will invalidate the paper and possibly lead to legal action.

Step Two: Locate A Notary And Have The Document Notarized

Next, you will want to locate a notary public to get the second half of the document filled out correctly. A notary public is most likely going to be at your local bank. You can also potentially find them by calling your regional government offices.

To be a notary public requires meeting state qualifications, taking a training exam, and being recognized by the state. As a result, it is difficult to impersonate one. Public records will oust anyone trying to lie on documents requiring a notary.

Step Three: Wait For Four To Six Weeks

Per Master Lock’s website, the standard time to wait for the factory reset combination is four to six weeks. If Master Lock is unable to do your lock, you can expect the response to be faster. However you get to open your lock, your next step will likely be to reset it. Having to repeatedly pick your lock to gain access to your key box would be a headache.

How To Reset Your Master Lock Key Box Combination

  • Open the key box
  • Push the reset button (or insert the reset tool) on the inside of your box
  • Rotate the number wheels to your preferred code
  • Close the key box

Step One: Open The Key Box

As you might expect, it is hard to reset the box without opening it. As a result, you will need to open it up before you can reset it. If you don’t remember the combination, check out the instructions mentioned earlier in this list. The combination is typically 0000 for new purchases. If that doesn’t work, check your owner’s manual.

Step Two: Push The Reset Button (Or Insert The Reset Tool) On The Inside Of Your Box

The inside of the box will typically have one of two methods for reset. First, there is a button that you can press down that allows you to reset the box. The button is the most typical option. Your other option is to find a reset tool that is with the initial purchase. The tool will resemble a small key that you can press to start the reset process.

Step Three: Rotate The Number Wheels To Your Preferred Code

After you press the button or insert the key, spin the box around so that you can access the numbers. Be sure that the box doesn’t close as you set the numbers to a unique code. When putting in the code, try to avoid things that are available on public access. Don’t use the last four of your SSN or the year you were born. Make sure it is nothing that people can guess.

Master Lock 5900d – What To Do If You Forget The Code

One largest key boxes you can get through Master Lock is the 5900d. Because it is still small in size, it follows many of the same techniques to open as the earlier how-tos we reviews. However, there are some reports that you can decode the lock by looking through the front. If that doesn’t help, use the same technique we mentioned earlier:

  • Place a thin pick in the gap of the number wheel of slot one
  • Wait until there is some give as you are rotating numbers to find the right setting
  • Do this with all four numbers until you find the right code.

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What If I Forget The Combination On My Master Lock Speed Dial?

Some YouTube videos are saying that you can remove the lock with a torque screwdriver. However, you do run the risk of destroying the lock by following those instructions.

Lock manipulation is also an option, but that involves pressing your ear to the lock and waiting to hear clicks. Given that the Speed Dial is a modern lock, you will have to be extra attentive for that to work. Lock manipulation requires years of training to master, don’t expect to do it in one go.

Honestly, the Master Lock Speed Dial is enough of a pain to suggest cutting out the middle man and buying a pair of bolt cutters. The replacement lock isn’t too expensive, and it will save you a lot of time that you could spend enjoying yourself.

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Eli Smith
Eli Smith

I'm a guy who becomes the expert of whatever I stumble upon, writing-wise. I've written tons about cool home products, home improvement, and smart technology in the home. I'm also the proud father of a kiddo born on new years, making my holidays very busy.

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