From DIY home security systems by brands like Ring to old faithfuls like ADT, our expert team at CNET has spent more than 100 hours testing and researching the best home security systems. Our current top pick is SimpliSafe, which has some of the best first-time security systems, with a range of options and tons of potential upgrades, including a beta service for AI-assisted monitoring agents.

If you want a security kit you can easily build out over a couple of years, Vivint is your best choice. We also have an excellent DIY option with Ring Alarm — no contract necessary and sporting a relatively affordable subscription plan — plus more picks for a variety of users.

Best starter kit home security system: SimpliSafe

We’ve tested the SimpliSafe system several times and most recently gave it a review score of 8.5 out of 10, one of our highest ratings for a home security system. If you’re looking for home security — without all the extra Wi-Fi and smart home integrations of the Ring Alarm kit — SimpliSafe’s easy-to-install, easy-to-use DIY system is a great option. It offers a comprehensive set of features, including equipment like security cameras and a very good mix of battery-powered motion detection sensors, all of which performed reliably well in our tests.

Starter kits begin at $280, or you can build a custom alarm system with the exact mix of devices you need. The security company’s monitoring plans start at $10 a month, but you’ll almost certainly want to spring for the $30-a-month professional monitoring service plan, which adds in things like 24/7 live guard protection, whole home monitoring, instant app alerts and faster response times.

Best build-as-you-go home security system: Vivint Smart Home

Vivint gives you a super-polished experience with third-party device integrations — and it doesn’t require a contract. The starter package includes only a touchscreen and a couple of sensors, but Vivint works well with voice assistants like Google Assistant and Alexa and supports a wide array of additional Vivint and third-party devices.

That’s great news if you’d like to add a compatible smart garage door, video doorbell or security camera system, but on your terms and timing. You can also adjust your budget based on what you’d like to buy now and purchase later. Vivint is the only brand with this approach, but it has one of the best offerings to begin with a starter kit and build from there.

Best DIY home security system: Ring Alarm 8-Piece Kit (2nd-gen)

Ring offers some excellent home security packages for users who want to take everything into their own hands, from picking out add-ons to choosing just the right spot on the wall. This eight-piece starter kit provides four important sensors, a base station plus a keypad, a motion detector and a range extender for those worried about Wi-Fi. We also like the Pro version of this package, but the second-gen kit is a bit newer and doesn’t force you to use the built-in router (we prefer picking out our own routers).

Amazon’s Ring devices include excellent Alexa support, and DIYers will like the largely intuitive management app. (If you’ve set up any smart devices before, these app controls will come easily to you.) In addition to direct controls and sensor notifications, users can also switch between home and away modes on the fly. If you decide to expand, almost any Ring product will be compatible including their security cameras and video doorbells, so it’s easy to level up.

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