Maybe your 10-year-old home security system still works perfectly fine, but it feels ancient compared to today’s smart home technology. You can’t check the status from your phone, receive instant alerts, or integrate it with other smart devices. The good news? In our experience, you don’t need to rip everything out to upgrade your existing home security system.
In this guide, we’ll give you proven upgrade strategies, compatible technologies, and cost-effective solutions that work with older alarm systems. We drew upon our decades-long industry experience and put together this guide on how you can breathe new life into your existing security system. We’ll also help you determine which upgrades make sense for your specific needs and budget. Let’s begin!
>> Learn More: The Best Home Security Systems of 2025
- Our very outdated ADT control panel that desperately needed an upgrade.
Understanding Your Current Home Security System
Before exploring upgrade options, you need to identify your existing alarm system’s components and capabilities. Most residential alarm systems installed between 2000 and 2015 share common layouts.
Assessing Your Security System’s Layout
Security systems installed in that era typically include a main control panel, at least one keypad, wireless door/window sensors, motion detectors, and sirens. The control panel serves as the brain. It processes signals from sensors and communicates with monitoring services through either landline or cellular connections. Landline connections are more common in older systems. If our memory serves us right, cellular security systems didn’t peak in popularity until after 2015.
When assessing your current security system, we suggest paying attention to these key factors and components:
- Control panel: Check the device’s manufacturer and model. Most likely, it’s from a third-party supplier (e.g. Honeywell, GE, 2Gig, etc.), installed by your alarm provider.
- Communication method: As mentioned, landlines are more common, but if you happen to have a cellular- or broadband-connected system, you’re in luck. You’d have an easier time updating your system with modern features like smartphone access.
- Sensors: Between 2008 and 2015, sensors were already mostly wireless. But if your security system was installed prior to 2008, you might still have sensors wired to a control box (usually in the basement or attic of your home).
- Keypad: Touch screen keypads weren’t very common back then. Most likely, you have an analog keypad (like the one pictured above). Check its functionality. If it can’t do much more than arm/disarm your system, it’s likely going to be the first one to be replaced.
- Monitoring agreement: This is also crucial. If your security system is currently being serviced by an alarm provider, check your security monitoring contract. It should tell you if you can switch providers without penalties. And who knows? You might even be eligible for a free or discounted equipment upgrade.
Pro Tip: We’ve seen home security system brands that offer loyal customers huge discounts when they upgrade to the latest hardware. We recommend giving your alarm provider a call to see what they offer.
Is Your Legacy Security System Compatible With Newer Solutions?
Not all legacy systems accept the same upgrade solutions. Compatibility depends on several technical factors that determine which enhancement options will work with your setup. Unfortunately, this is a broad spectrum. Before even offering your upgrades, security system installers will need to check things like communication protocols, zone capacity, and power requirements.
Your legacy system might not be compatible with newer solutions if:
- The control panel and sensors use a proprietary communication protocol, especially if it’s now considered obsolete (or near-obsolete), such as Ademco Contact ID.
- The control panel has limited zoning capabilities (i.e., number of sensors it can connect to). It’s common for older systems to have only 8 to 32 zones, whereas newer systems can connect to hundreds of sensors.
- The control panel requires wired sensors. While there are still hardwired security systems, wired sensors are very rare.
Expert Tip: Check your control panel’s model number and search the manufacturer’s website for upgrade compatibility guides. Most major brands publish detailed compatibility matrices for their legacy products.
Upgrading Your Smart Home Capabilities
Our Vivint security system is 100 percent cellular, but requires professional installation to work.
By now, you should have a clearer idea of whether it makes more sense to upgrade or replace your existing home security system. If you choose to upgrade, let’s talk about the different types of upgrades you can make, starting with smart home capabilities.
Smart home-enabled security systems – such as our Vivint system pictured above – have smartphone app control, remote monitoring, smart device integrations (smart lights, locks, thermostats, etc.), and automation features. There are a few ways you can incorporate some or all of those features into your existing alarm system.
Retrofit Smart Modules
Smart retrofit modules connect directly to existing control panels, creating a bridge between legacy hardware and modern smart home platforms. These devices translate traditional alarm signals into smart home commands, enabling smartphone control and alerts.
We’ve found that retrofit modules typically cost between $150 and $400, compared to $800 and $2,000 for complete security system replacement. Just note that installation complexity and compatibility vary. In our experience, smart modules work best with security systems that are already wireless to begin with. If yours fits the bill, installation shouldn’t take more than an hour.
We suggest looking for a smart module with built-in home automation capabilities as well. Since you’ll use the module’s companion app (not your alarm provider’s) to control and monitor your security system. Might as well use a module that supports third-party smart home integrations and other modern features such as Alexa or Google Assistant voice control.
>> Learn More: The Best Smart Home Automation Security Systems in 2025
Smart Sensor Additions
If retrofitting a smart module sounds like too much work, we recommend looking into a simpler sensor upgrade. Entry and motion sensors are the most common sensor types available to legacy systems, but back then, they were one-trick ponies. Entry sensors detected the opening and closing of doors and windows, and motion sensors detected moving heat signatures. Nothing more, nothing less. Today, we’re seeing entry and motion sensors that are slightly smarter.
In addition to detecting the opening and closing of doors and windows, some entry sensors can now detect vibration. This means they can alert you in case someone tries to break your door.
PIR motion sensors now also have adjustable sensitivity. This functionality would allow you to adjust the sensitivity to reduce false positives. It’s particularly handy if you have pets. The best pet-friendly security systems we’ve tested have motion sensors you can configure to ignore pets up to 80 pounds.
We also recommend adding environmental sensors such as smoke, carbon monoxide, and flood detectors, especially if your alarm system is monitored. Unlike traditional smoke alarms, smoke alarms paired with a monitored system can automatically call for help when they detect fire.
FYI: Most legacy panels support 8 to 32 zones, but many installations only use 6-10 zones. If your panel has unused zones, we recommend using them to connect additional sensors and expand your security system’s detection capabilities.
Communication Method Upgrades
Legacy alarm systems often struggle with outdated communication methods that limit functionality and reliability. We recommend considering an upgrade to modern communication technologies to improve system performance.
>> Find Out: Does My Wireless Security System Still Work If the Internet Goes Out?
Upgrading to Cellular Communication
If your system uses a landline for communication, consider upgrading it to cellular. Landlines are unreliable. Simply cutting landline wires to your home can make your system unable to send alerts. Meanwhile, cellular signals are wireless, which means there are no wires to cut.
Cellular communication also enables advanced features such as crash and smash protection. If someone tampers with your security system and the cellular signal is cut, your alarm provider’s monitoring center will receive a tamper alert. We saw this feature when we recently tested Frontpoint’s cellular security system.
Here are some other benefits of upgrading to cellular communication:
- Faster alarm transmission (10 to 15 seconds vs. 45+ seconds for landline)
- Can work as a backup communication to a landline
- Two-way communication capabilities for remote troubleshooting
- Enhanced security against line cutting
To upgrade to cellular communication, you’d most likely need a cellular module that works with your control panel. Your alarm provider might even have the right hardware. Just note this upgrade will likely increase your monthly monitoring fee.
Upgrading to Broadband Internet Communication
Our Managing Editor testing an internet-connected ADT control panel.
Besides cellular signals, modern security systems can also use broadband internet to communicate. It’s not exactly as reliable as cellular communication. As we all know, internet outages are pretty common. Plus, if your home has a wired internet connection, it’d be as easy to cut as a landline.
However, a security system that communicates via the internet has distinct advantages. You’d be able to include security cameras, for example, that can stream live videos to your smartphone. It also opens you to the possibility of using modern features such as home automation and voice control.
Unfortunately, giving your legacy control panel internet access isn’t as easy as adding a cellular module. In most cases, you’d need a smart module (discussed above), which means you’ll use a third-party app to control most functions moving forward.
Dual-Path Communication Systems
This SimpliSafe base station both connects to the internet and uses cellular communication as backup.
Dual-path systems combine the two previously discussed communication technologies. They use internet communication as the primary method, and then switch to cellular backup when the internet is down. The SimpliSafe security system we reviewed is one example of a system with dual-path communication. We recommend this type of communication protocol because it’s the most reliable.
While we are yet to see a device dedicated to this kind of upgrade, most smart modules available on the market come with backup cellular connectivity.
Monitoring Service Enhancements
Beyond hardware upgrades, you can also make enhancements to how your legacy security system is monitored. Traditional monitoring services have evolved significantly. Modern monitoring options provide more value and better security, while often reducing monthly costs. If your original monitoring contract has expired, it might be time to look into switching to a different plan or a different alarm provider (a.k.a. alarm takeover).
Current professional monitoring services offer capabilities far beyond basic alarm response. We’re seeing advanced monitoring centers that use artificial intelligence in security cameras to reduce false alarms and provide faster emergency response coordination.
If you decide to switch to a different monitoring provider, we recommend looking for a brand that can offer you features such as:
- Video verification: Cameras confirm actual emergencies before dispatch, speeding up police response1
- Smart home integration: Coordinate with lights, locks, and climate systems
- Mobile app control: Arm/disarm, receive alerts, and view system status
- Environmental monitoring: Track temperature, humidity, and air quality
Take note, however, that the features they can offer you will depend on your hardware. They can’t give you smart home integrations and mobile app control, for example, if your legacy system simply doesn’t support it.
>> Read More: The Best Home Security Systems With No Monthly Fees
Adding Smart Home Features
Smart home integration transforms legacy alarm systems into comprehensive home automation platforms. This is the ultimate upgrade, but from what we’ve seen, not all legacy systems can support smart home features. These upgrades are best for security systems installed after 2015, and even then, you might need to install a smart module to integrate some of these devices.
In any case, let’s take a look at some smart home components and features that provide the best value.
We recommend including smart locks in your legacy alarm system upgrade.
Smart Lock Integration
Smart locks can integrate with upgraded alarm systems to provide automatic locking when the system arms and unlocked access for trusted users. This integration requires compatible smart locks and a communication bridge. Some of the features you’ll gain are:
- Automatic lock/unlock based on alarm status
- Temporary access codes for guests
- Mobile notifications for lock/unlock events
- Emergency unlock during fire alarm activation
Some of the best smart locks we’ve tested come from August, Yale, and Schlage, with many models designed for alarm system integration.
Lighting and Climate Control
Smart lighting and climate systems can respond to alarm events and system status changes. These integrations enhance security while providing energy savings through automated schedules. Some common automation scenarios include:
- Away mode: Lights simulate occupancy when system is armed
- Alarm response: All lights activate during security events
- Temperature control: Adjust climate settings based on occupancy detection
- Energy savings: Reduce heating/cooling when nobody is home
Voice Assistant Compatibility
Modern alarm system upgrades often include voice assistant integration, allowing control through Amazon Alexa, Google Assistant, or Apple HomeKit. Using your voice, you can:
- Arm/disarm system with voice commands (requires additional security verification)
- Check system status and sensor conditions
- Receive spoken alerts for alarm events
- Control integrated smart home devices
Security considerations require most voice assistants to use additional authentication for sensitive commands like disarming the alarm system.
Cost-Benefit Analysis of Upgrades vs. Replacement
We’ve shown you that there are plenty of possibilities if you want to upgrade a legacy home security system. But is it really the most practical route for you? Let’s do a quick cost-benefit analysis of upgrading versus replacing your current security system.
How Much Does It Cost to Upgrade A Legacy System?
Legacy system upgrades typically cost up to 40 percent of full replacement, while providing as much as 80 percent of the functionality. The costs you’ll need to consider are:
| Upgrade Type | Cost Range | Installation | Total Investment |
|---|---|---|---|
| Smart module retrofit | $150-400 | $100-200 | $250-600 |
| Cellular communicator | $200-350 | $150-250 | $350-600 |
| IP communication | $150-$400 | $100-200 | $250-600 |
| Smart sensor additions | $50-150 each | $75-125 each | $125-275 each |
| Professional monitoring upgrade | $0-100 | $0-50 | $0-150 |
How Much Does It Cost to Replace A Legacy System
Complete alarm system replacement involves significantly higher upfront costs but provides the latest technology and the longest future viability. Full replacement costs vary depending on the type of system you need:
- Basic professional system: $500-$1,000 installed
- Mid-range smart system: $1,000-$2,000 installed
- Premium integrated system: $2,000-$3,000+ installed
Additional replacement costs include potential wall repair, repainting, and disposal of existing equipment.
Cove is an affordable security system on the market, especially when the company is running a sale.
Conclusion: Upgrade or Replace?
Whether you should upgrade or replace your legacy security system depends on a number of factors, including its age, supported functionality, and equipment condition. In some cases, meaningful upgrades are more practical. They are cost-efficient, and they let you enjoy much of the modern security system features we’re seeing in 2025 security systems.
Just remember that security technology continues evolving rapidly. Choose upgrade components that support future expansion and integration to maximize the value of your enhancement investment over time.
Frequently Asked Questions
Most systems over 20 years old have limited upgrade options due to outdated communication protocols and component availability. Consider replacement for systems this old to ensure reliability and access to modern features. Most insurance companies continue existing discounts for upgraded systems, and some offer additional discounts for smart features like video verification. Contact your insurer to confirm specific discount eligibility. Quality upgrades typically provide 7-12 years of reliable service, similar to complete system lifespans. Component quality and maintenance frequency significantly impact longevity. Yes, many monitoring service upgrades work with existing hardware, though some advanced features may require communication module updates. Check with potential monitoring companies about compatibility with your specific system. Most upgrades don’t require permits, but electrical modifications might need inspection depending on local codes. Check with your municipality about specific requirements for security system modifications. Yes, properly configured upgraded systems include battery backup that maintains operation during power outages. Battery backup can typically keep a security system for eight to 24 hours.
