2020 Update

Although more than a year old, all of the information in this article is still relevant. Changing the master code of your security system can be very helpful, scroll down to find out how. 


More than 2 million homes are burglarized every year. Having a home security system can keep your family safe. The ADT security system is one device that can help to protect your family from potential threats. Periodically, you may need to change the master code in order to safeguard your home.

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    Why Is a Master Code Important?

    You’re here because you want to change the master code on your alarm panel. It’s critical you follow the steps below for implementing this change because you master code plays a fundamental role in the overall safety and security of your home. For example, the master code allows you to arm or disarm your entire system; you can also use your master code to change key features and functions of your home security system. Another great thing about the master code is that it gives you the ability to add, delete, and alter the access codes to the system.

    Similar to the other important passwords you may use for handling sensitive information, like banking personnel, you should change your master code every so often. This will ensure maximum security and promote the overall safety of your home.

    Changing the Master Access Code

    Using the ADT system, you will need to change the master access code in two ways the first is through the ADT Pulse Portal. The second way is on your system’s keypad.

    The first thing you will need before beginning is the current master code. There is no way to change it without knowing what the current numbers are. Without the current master code, you will have to contact ADT to acquire this code. Depending on the type of system, you’ll be able to reprogram it in just a few easy steps.

    A woman is changing the master code on the alarm panel in her home.

    Using the ADT Portal

    Once you reach the ADT Pulse Portal page, enter your username and password. Find the System tab and then click on the name of your security system.

    Click on the Change button and then you will see the Security Panel Access Code window. In the New Master Code field, type in the code you want to create and then re-type it in the box below. You will then see a Password box. Enter the password for the ADT Pulse Portal and then click the Save button.

    If you have additional questions about changing the master code through the ADT Portal, refer to your user manual or contact ACT’s customer support team.

    Changing the Code on the Keypad

    First, on the keypad, press the asterisk symbol (*) and then 5. Enter your current master code. The yellow system light will flash after the red light signals that the system is armed.

    Next, depress the number 40. You will need to know which model you own for this particular number.

    Then, enter a new master code. This number should be between four and six digits. Once this number has been entered press the pound or hashtag key (#).

    You should test this code a few times to make sure it works perfectly.

    If you have additional questions about changing the master code on your keypad, refer to your user manual or contact ADT’s customer support team.

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    Reasons to Change the Master Code

    There are many cases where changing your alarm panel’s master code is a must.

    Maybe you’re in the middle of an unfortunate breakup. Sure, you may have gotten the key back from your ex, but just in case, you decide to change the locks. While this is an important step, you also shouldn’t forget to change the master code on your security system, too.

    You don’t want to come home one day to find all of your furniture missing because he or she wants revenge or just can’t let go.

    According to the U.S. Department of Justice, 3,424,100 individuals are stalked every year and “the risk of stalking victimization was highest for individuals who were divorced or separated—34 per 1,000 individuals.”

    Another reason you should change the code is to prevent a former employee from entering your home at their leisure. Maybe a babysitter stops by twice a week to watch the kids or maybe an interior decorator visits to work on a task. Once the babysitter or interior decorator’s job is finished, they should no longer have unfettered access to your home.

    Other reasons you should change the master access code include:

    • Your child or friend gave this code to other people that you don’t know
    • You forgot the code and need to have it changed
    • You want to restrict certain people from entering your home

    Are you ready to stop unauthorized intrusions from your home? Contact the professionals at Protect America. They can offer you a free quote for their home protection services.