Key points
- Commands from a phone, speaker or hub reach Matter devices over the home’s own network, not through a cloud service.
- The Connectivity Standards Alliance (CSA) says Matter devices keep working within the local network if the internet connection goes down.
- Control from outside the home needs an internet-connected controller in the home, such as a smart speaker or hub.
- Google Home and Alexa need a hub or Echo before you can add a device. Apple’s Home app can add and control devices without a hub from iOS 18, but needs one for remote control, sharing and automations.
- Matter devices on Thread also need a Thread border router.
Matter local control during outages
Matter keeps working when the internet goes down because its traffic never needed the internet in the first place. The CSA describes Matter as a local connectivity technology, and the open-source Matter SDK describes it as an application layer built on IP. A controller and a device on the same network talk to each other directly.
The platforms say the same in their own documentation. Google’s help page explains that Matter-enabled devices carry out commands over the existing home network rather than over the internet, and its developer documentation contrasts Matter’s local path with the higher latency of a cloud-to-cloud connection. Amazon says its Echo devices connect Matter devices to Alexa locally. Home Assistant says device control works with no internet connection or cloud services.
The CSA put it plainly in April 2025: even if the internet connection goes down, Matter devices maintain functionality within the local network.
Matter features that need the internet
Three things in a Matter home commonly need the internet.
- Control from away from home. The CSA’s FAQ says Matter-only devices need an internet-connected controller in the home, such as one built into a smart speaker or hub, to be controlled while you are away.
- Some setup and sharing steps. Each ecosystem adds devices through its own app, and some require a hub first. Google’s help page says you need a Matter-enabled hub on the home network, added through the Google Home app, before adding Matter devices. Amazon says a compatible Echo must be set up before a Matter device can be added in the Alexa app.
- Fetching software updates. Matter includes an over-the-air (OTA) update mechanism. The Distributed Compliance Ledger, the CSA’s public record of certified products, can list the URL where each software version’s update image is obtained, so the device that downloads it needs to reach that address.
None of these affects a device that is already set up and being controlled from inside the home.
Local dependencies of a Matter home
Local control removes the internet from the path, but not the local network. A Matter home depends on these staying up:
- One shared network. The CSA says Matter was designed to have all devices on the same network so they can talk directly. Putting devices on a guest network that is isolated from the controller breaks setup and control.
- The controller or hub. Apple says a home hub (HomePod, HomePod mini or Apple TV) must be at home, on the home Wi-Fi and powered on to provide remote control, sharing and automations.
- A Thread border router, for Thread devices. OpenThread says a Thread network requires a border router to connect to other networks, and Apple says Thread-enabled Matter accessories need a Thread-enabled home hub. Matter vs Thread covers why.
- Power. Routers, hubs and border routers on mains power stop during a power cut unless they are on a backup supply, and the devices that depend on them stop with them.
Matter local control by ecosystem
Apple, Google, Amazon, SmartThings and Home Assistant all control Matter devices locally, but they differ on what you need before adding a device. This table records what each one’s own documentation said in October 2026.
| Ecosystem | What you need to add Matter devices | What its documentation says about local control |
|---|---|---|
| Apple Home | An iPhone on iOS 18 or later can add and control devices with no home hub; a home hub is needed for remote control, sharing and automations | Thread accessories need a Thread-enabled home hub |
| Google Home | A Matter-enabled hub on the home network, added through the Google Home app | Commands travel over the home network rather than the internet |
| Amazon Alexa | A compatible Echo, which acts as the Matter administrator | The Echo connects Matter devices to Alexa locally |
| Samsung SmartThings | A SmartThings hub, or one built into a recent Samsung TV, monitor, refrigerator, soundbar or SmartThings Station | Not stated on the partner page checked |
| Home Assistant | The Matter Server app, with devices added through the Companion app | Device control works with no internet connection or cloud services |
The pages checked for this article do not say which voice features or automations keep running during an outage in Google Home, Alexa or SmartThings. Treat that as something to test, not something to assume.
Testing a Matter setup offline
Test a Matter setup the way an outage would. Disconnect the internet at the router, not the home Wi-Fi, so the local network stays up. Then:
- Control each device from a phone on the home Wi-Fi, from each ecosystem you use.
- Trigger each automation you rely on, such as a sensor turning on a light.
- Check that battery devices on Thread still report, which confirms the border router is working.
- Restart the hub or controller while the internet is still off, and repeat the first step. A controller that cannot start without the internet fails this step.
- Reconnect the internet and confirm that remote control and any cloud features come back.
Anything that fails during the test depends on the internet, whatever the box says. Can a smart home run without the cloud? applies the same test to Zigbee, Z-Wave, voice control and each ecosystem as a whole.
Offline Protocol and Matter
Matter keeps a home’s devices controllable over the home’s own network. It assumes the controller and the devices share one IP network, and it standardises what certified devices are and how they are controlled.
Offline Protocol does a different job. It is an SDK that lets apps on phones, computers and gateways discover each other, verify each other’s identity and exchange encrypted messages, shared documents and service calls, over Bluetooth LE, a local network or a relay, including between devices that share no network at all. It is not a Matter controller and does not control Matter devices. An app can use both, with a Matter controller for the devices and Offline Protocol for the people and apps working around them.