Does a smart home work without internet? Local control

Your internet goes down, you tap the light switch in the app, and nothing happens. Or it does. Whether a smart home keeps working offline depends far less on the brand of bulb than on where the decisions are made: on a company's server, or on a device inside your home.

This guide explains the difference between cloud and local control, what typically keeps working during an outage, and how to choose devices so a broken connection doesn't leave you in the dark.

Cloud control vs local control

With cloud control, your phone or speaker sends a command to the manufacturer's server over the internet, and the server sends it back down to the device. It's simple for companies to build and makes remote access easy. The catch: if your internet connection, the company's servers or the company itself goes away, the device can stop responding to the app.

With local control, the command goes from your phone, a wall switch or an automation straight to a hub or the device over your home network. The internet is only needed for extras like remote access. Local control is also usually faster, because the signal doesn't make a round trip to a data centre.

What usually works without internet

Exact behaviour varies by product, but here's what you can generally expect when the internet drops but the power stays on:

• Physical controls. Smart bulbs still respond to wall switches and smart buttons that are paired directly or through a local hub. A smart plug's button still toggles it.
• Zigbee, Z-Wave and Thread devices keep talking to their hub, because these radio networks work inside your home. A Philips Hue Bridge, for example, controls its lights over your local network, so the Hue app usually still works when your phone is on the same Wi-Fi.
• Matter devices are controlled over your local network by a Matter controller, which is why Google has been moving Hue lights to local Matter control in Google Home. Read our Matter and Thread explainer if the terms are new.
• Automations on a local hub such as Home Assistant or many dedicated hubs: motion lights, schedules and sensor triggers keep running.
• Smart locks usually still open with a keypad, key, fingerprint or Bluetooth. Our smart lock guide explains what to look for.
• Thermostats keep following their schedule and can be adjusted on the device itself.

What usually stops

• Remote access. Controlling anything from outside the house needs internet, local system or not.
• Most voice assistants. Popular assistants process many requests in the cloud, so voice commands are often unavailable or limited offline.
• Cloud-only Wi-Fi gadgets. Cheap plugs, bulbs and cameras that only work through a vendor app often can't be controlled at all.
• Cloud camera recording and alerts. Cameras that upload clips to a subscription service can't do it offline. Models with a microSD card or a local recorder can keep recording; see our home security camera guide.
• Firmware updates and integrations with other companies' services.

How to build a smart home that keeps working offline

1. Check for local control before you buy. Look for Matter support, or Zigbee, Z-Wave or Thread devices that work with a hub you own. Be wary of devices that only work through a vendor's cloud app.
2. Run automations on a local hub. A smart speaker hub, a dedicated bridge or a Home Assistant box can run routines in your home rather than in the cloud. Check that your platform actually executes them locally.
3. Keep physical controls. Smart switches or wireless buttons mean guests and family can always turn lights on, app or no app.
4. Make your home network solid. Local control depends on Wi-Fi and the hub. A good router or mesh Wi-Fi system and a fixed spot for the hub reduce dropouts.
5. Back up power for the core. A UPS for the router, modem and hub is cheap insurance.
6. Test it. Unplug the internet cable from your router for ten minutes and see what still works. It's the quickest way to find the cloud-dependent devices.

Is local always better?

Not for everything. Cloud services are convenient for remote access, sharing with family, voice control and storing camera footage off-site, which helps if a camera is stolen. The best setup for most homes is local first, cloud as a bonus: the basics run inside your house, and online features add convenience on top.