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What is a Master Key System and How Does it Work

instakey master key system how does it work blog

Every organization wants to maintain the security of their employees, goods, and facilities. Despite advancements in digital technology, there’s no more effective way to keep your company physically secure than with locks and keys. It can also be much more cost-effective. The effectiveness and security of your key system is called key control.

Creating the most secure and effective key control for your organization includes a few different components. One of those is your master key system. Master keys provide high-level access and streamlined day-to-day key management for employees and stakeholders who need to be able to easily open many doors.

What is a Master Key?

A master key is a key that gives you access to more than one door or lock within your organization. Typically, master keys are given only to high-level stakeholders at a specific location. For example, a Facility Manager may have a master key that can open all doors at their location while employees have sub-master keys that only open a single door or limited doors depending on their need for access. 

Master keys are designed to simplify the key needs of someone with high-level access within an organization. Without one key that can open many doors, facility managers have to carry all the keys needed to open every door. This is inefficient and can easily become a security breach if a key ring is lost. With a master key, a facility manager can carry a single key and retain access across an entire location.

What is a Master Key System? 

A master key system is the master keys, locks, users, and hierarchy that make up your day-to-day key management for master key holders. While a single master key can give high-level access to a single user, your master key system determines how securely your entire organization is using their master keys at all levels of master key access. 

Master Key Levels

While a master key traditionally refers to a key that can open all doors or access points in a building, the capabilities with master keys have changed to include differing levels of master key access. This allows organizations with many locations to provide different Facilities Managers or LP/AP/Security Managers with only the access they need for their building or area, while limiting unnecessary access at higher levels. For companies with many locations and employees managing each location separately, like grocery or big box retail and vendor keys for restaurant chains, using master keys is necessary to avoid having dozens if not hundreds of keys per location to keep track of. 

By designating various levels of master key access, you can maintain tighter security. Most master key systems will have between two and five levels of access. Here are the commonly used designations for master key levels:

  • Great Grand Master Key

This is typically the highest level access for a master key system. A great grand level master key (GGMK) has access to your entire organization, including facilities, locations, doors etc. This key can open all the access levels beneath it. Great grand master keys should be limited to a very limited number of stakeholders within your organization who need complete access. The fewer people who have high-level access to your company’s physical locations, the more secure your master key system can be.

  • Grand Master Key

A grand master key (GMK) is the next tier down of master level access. It has a higher level of access than master keys but cannot open all the doors a great grand master key can. Grand master keys are often used as a corporate master key for all multi-site location’s access. Master Keys should also be limited to only a few stakeholders within your organization.

  • Master Key

A master key (MK) holder is able to open all locks below it in the system but cannot open locks associated with great grand master or grand master keys. Master keys can be designated for key holders who need a high-level of access within their level they can also be used as a sub-master. This can be a District, Regional or Area Manager that opens all locks at facilities in their area but doesn’t open locks at facilities outside of their access level or area. Please keep in mind that if your organization realigns a territory or area, this can cause complications along with the need to rekey to keep keys from opening facilities that the manager should not be able to access. It is always recommended to go with an option where the geography does not change, such as a state master.

  • User Key

User keys are another way of referring to the normal keys you distribute to employees who don’t need high-level access. Typically, user keys are associated with a single lock, like a front door or storage room. They can’t open any other doors and are the lowest level of keyed access to your organization.

Master Key System Schematic

Master keys are related to one another in a hierarchy. Your master key system schematic is a diagram or blueprint that allows you to visualize your master key security across your entire organization. The schematic is used to establish your master key system. Once approved by your organization, it is used by your key control partner to mathematically key cylinders and cut keys. Creating a schematic allows you to determine how your master key system will be organized, how many master keys you need, and who will be designated as master key holders before the keys are cut. 

Master Key System Security

Your master key system is a part of your larger key control. Like the user keys you hand out to employees, there are some best practices to put into place with your master keys. Restricted keys, user-rekeyable cores, and key tracking software can help to enhance the security of your master key system and there is money to be saved on rekeys. With a master key system, there is a risk of needing a complete rekey of a facility or facilities in the event a high-level master key is lost or stolen. Having user-rekeyable cores allows locks to be rekeyed only on the master level affected. This would be a significant reduction in rekey costs.

By maximizing security with every component of your key control, you can trust that your products, employees, and facilities are safe and secure. InstaKey provides a comprehensive key control program, with a dedicated partnership to enable the very best keyed security the industry has to offer. Our innovative technology and restricted, serialized keys allow for the highest level of physical security and cost control. 

Check out our explainer video on Master Key Systems


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