Can a smart home run without the cloud?

When the internet goes down, anything whose commands travel through a company’s servers stops, and anything controlled from inside the home keeps going. Most homes have both kinds, which is why the same outage can leave the lights working and the camera app blank.

These parts usually depend on the internet:

• Devices controlled through the maker’s cloud. The phone app sends a command to the maker’s servers, which forward it to the device. When the home loses its connection, that path is gone even though the phone and the device sit in the same room.
• Control from away from home. The Matter FAQ says control from outside needs an internet-connected controller in the home, and Apple and Google both tie remote control to a home hub.
• Cloud voice assistants and cloud-to-cloud links. A request that is processed on a company’s servers, or a skill that links two companies’ clouds, needs the connection at both ends.
• Setup, accounts and software updates. Several ecosystems add devices through an app tied to an account, and devices fetch updates from the internet.

These parts keep working as long as the home network, the hub and the power stay up:

• Matter devices. The Connectivity Standards Alliance (CSA) said in April 2025 that Matter devices maintain functionality within the local network if the internet connection goes down. Does Matter work without internet? covers that case in detail.
• Zigbee devices. The CSA’s Zigbee FAQ says Zigbee’s local connectivity still works if the internet is down and does not need the cloud.
• Z-Wave and Thread devices, which talk to a hub or border router in the home over their own radios.
• HomeKit devices. Home Assistant’s documentation says a device’s HomeKit API won’t break if your internet connection goes down or the cloud service goes away.

Matter, Zigbee, Z-Wave, Thread and HomeKit all control devices from inside the home. None of them needs a cloud service in the command path. They differ in what they are:

• Matter is an application standard that runs over Wi-Fi, Thread or Ethernet on the home’s IP network.
• Thread is a low-power IPv6 mesh network that Matter devices often use. It reaches the rest of the home through a Thread border router.
• Zigbee and Z-Wave are mesh networks with their own radios, so their devices talk to a hub or a USB coordinator rather than to Wi-Fi.
• HomeKit is Apple’s accessory protocol, which Home Assistant can also control directly.

Matter vs Zigbee vs Z-Wave vs Thread compares the four side by side. Wi-Fi devices that do not use Matter or HomeKit vary by maker: some offer a local interface, many are controlled only through the maker’s cloud.

Local control sends the command from a phone, hub or speaker in the home straight to the device. Cloud control sends it out to the maker’s servers and back in again, so it needs the internet at the moment you press the button.

The ecosystems describe the benefit of the local path in their own words. Google’s help page says Matter commands go directly over your home wireless network to the device rather than through the cloud. Amazon says a local Matter connection lets Alexa control a device locally, reducing latency and improving reliability.

Home Assistant puts a label on every integration that makes the difference visible. Its developer documentation defines the IoT classes this way:

A device with a cloud class stops updating when the internet does, even inside an otherwise local home.

Some “local” devices still contact the cloud during setup because adding a device and controlling it are different steps, and the setup step often runs through an ecosystem’s app, account or phone services. Once a device is added, control can stay local.

The documentation names several reasons:

• The phone’s Matter support comes from a platform service. Home Assistant’s Matter page says the Android Companion app adds Matter devices through Google Play services, that versions of the app without Google Play services can’t add Matter devices, and that it can take up to 24 hours for Google Play services to download the Matter modules. That is why a Home Assistant user can see traffic to Google while adding a device that will then run locally.
• Some makers require an account first. Home Assistant notes that some vendors require you to set up an account before you can enable Matter support on some products, especially their own branded hubs and bridges.
• Some ecosystems need a hub added through their app. Google’s help page says you need a Matter-enabled hub on the home network, added through the Google Home app, before you can add Matter devices.
• Updates are fetched from the internet. Home Assistant checks the CSA’s Distributed Compliance Ledger for Matter firmware updates every 12 hours by default.

None of this changes how a device behaves once it is set up, but it does mean that a home with no internet at all is harder to build than a home that keeps working when the internet drops.

All five major ecosystems control at least some devices locally, and they differ most on hubs, remote access and voice. This table records what each one’s own documentation said as of October 2026. “Not stated” means the pages checked do not say, not that the feature is missing.

If a cell matters to you, test it at home with the internet unplugged rather than relying on any table, including this one.

Home Assistant runs on hardware in your home and talks to devices directly, through integrations that are labelled local or cloud. Its own documentation says Home Assistant works fully without its cloud service, which exists for remote access, the Google Assistant and Alexa integrations, and cloud speech engines. (The page notes that Home Assistant Cloud is planned to be renamed Home Assistant Link on 2 December 2026.)

A typical local setup has four parts:

1. The Home Assistant server, on a dedicated box, a small computer or a virtual machine.
2. Radio adapters for the networks Wi-Fi cannot reach. Zigbee devices join through a USB Zigbee coordinator, Z-Wave devices through a Z-Wave adapter, and Thread devices through a Thread border router, which can be Home Assistant itself with its OpenThread Border Router app or a speaker or hub you already own.
3. Local integrations for everything else, such as the Matter integration and the HomeKit Device integration, both of which Home Assistant lists as local push.
4. The Companion app on your phone, which controls the home over the local network and is used to add Matter devices over Bluetooth.

Home Assistant also notes that a maker’s own local integration can beat Matter: Matter exposes only basic light controls for Philips Hue, while the native Hue integration, which also runs locally, supports Hue’s scenes and entertainment features.

Voice control works without the cloud if the speech recognition runs on your own hardware, and among the major ecosystems only Home Assistant documents a fully local voice pipeline. Its guide says Assist can run entirely on your own hardware so spoken commands never leave the home.

Home Assistant offers two local speech-to-text engines and one text-to-speech engine:

• Speech-to-Phrase recognises a fixed set of home control phrases. Home Assistant says it transcribes in under one second even on a Home Assistant Green or Raspberry Pi 4, but supports only a subset of Assist’s commands.
• Whisper tries to transcribe everything. Home Assistant says it takes around 8 seconds per command on a Raspberry Pi 4 and under a second on an Intel NUC, so it suits more powerful hardware or a setup that pairs Assist with a language model.
• Piper speaks the answer. Home Assistant says it generates 1.6 seconds of speech per second on a Raspberry Pi with medium-quality voices.

Devices must also be exposed to Assist before it can control them. Apple says Siri Settings indicates whether requests are processed on the device, but none of the Apple, Google or Amazon pages checked for this article say which home control requests work with the internet down.

To check that a device works locally, look at its protocol, how your hub integrates it, and whether setup needs an account, and then test it with the internet unplugged while you can still return it.

1. Look for a local standard on the box or listing: Matter, Zigbee, Z-Wave, Thread or Works with Apple Home. Each of these is controlled from a hub or controller in the home.
2. If you use Home Assistant, read the integration’s IoT class. Local push or local polling means it talks to the device directly. Cloud push or cloud polling means it stops updating when the internet does.
3. Read the setup instructions for an account requirement. If the maker’s app must create an account or link a cloud before the device can be added, expect setup to need the internet even if control later does not.
4. Check what your controller needs. Google Home needs a Matter-enabled hub, Alexa a compatible Echo, Apple a home hub for automations and remote control, and Thread devices a border router.
5. Test it after setup. Disconnect the internet at the router, leaving the home Wi-Fi on. Control the device from a phone on the home network, trigger an automation that uses it, and restart the hub while the internet is still off. Does Matter work without internet? has the full test.

Offline Protocol is not a smart home platform. It does not control lights, locks or thermostats, and it does not speak Matter, Zigbee, Z-Wave, Thread or HomeKit.

What this article teaches is the principle the SDK is built on: the devices that are present do the work, and the cloud is optional. Offline Protocol applies that to apps rather than appliances. 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, the local network or a relay, so the people and machines at a site keep coordinating when the connection drops. How do devices coordinate locally beyond the smart home? covers that kind of site.