Home Assistant runs locally on your own hardware, so it keeps working even when your internet goes down
Home Assistant is software that controls smart home devices — lights, thermostats, cameras, locks — from a central hub in your house. Because it runs on a device you own and control, sitting on your own network, it does not need internet to function. When your internet connection drops, Home Assistant continues to control devices that are also on your local network. You lose remote access (checking your home from work, for example), but the core system keeps running.
This is different from cloud-based systems like Google Home or Amazon Alexa, which send commands through the internet to company servers, then back to your devices. Those systems stop working the moment your internet fails. Home Assistant avoids that problem by design.
Key Takeaways
- Home Assistant runs on hardware in your home and controls devices over your local network, so internet outages do not stop it from working.
- You lose remote access when offline — you cannot check cameras or control lights from outside your home — but local control continues.
- Devices must be on the same local network as Home Assistant to work without internet; devices that only work through the cloud will not respond.
- Internet is useful for automations that depend on outside data, like weather forecasts or traffic conditions, which will not update during an outage.
- Setting up Home Assistant requires a dedicated device like a Raspberry Pi or an old computer, plus some technical setup on your part.
What stops working when internet goes down
Remote access is the main thing you lose. If you are away from home and your internet fails, you cannot open the Home Assistant app on your phone to check a camera, unlock a door, or turn on a light. The system is still running and controlling devices at home, but you have no way to reach it from outside.
Automations that depend on outside information also pause. If you have a rule that says "turn on lights when sunset happens," Home Assistant needs internet to know when sunset is in your location. Weather-based automations, traffic-based automations, or any rule that pulls data from the internet will not work during an outage. straightforward automations — "turn on this light when this motion sensor detects movement" — keep working because both the sensor and the light are local.
Some integrations (connections to specific services or devices) require internet even for local control. If a device only communicates through its manufacturer's cloud service, Home Assistant cannot control it locally no matter how you set things up. You need devices that work on your local network directly.
Which devices work without internet
Devices that use local protocols — Zigbee, Z-Wave, Matter, or direct WiFi commands — work without internet because they talk directly to Home Assistant over your home network. Zigbee and Z-Wave are radio protocols that do not use the internet at all; they communicate only within your home. Matter is a newer standard designed for local control. Many WiFi devices can also be controlled locally if they support the right protocol.
Devices that only work through the cloud — like some older smart plugs or cameras that require their manufacturer's app and servers — will not respond to Home Assistant commands when internet is down. Before buying a device, check whether it supports local control or requires internet.
Home Assistant itself can work with both types, but only local devices will respond during an outage. You might have a mix: some Zigbee lights that work offline, and a cloud-based camera that does not. The local ones keep responding; the cloud ones do not.
How to set up Home Assistant for offline use
Home Assistant runs on a dedicated device in your home — usually a Raspberry Pi (a small, inexpensive computer), an old laptop, or a purpose-built Home Assistant device. This hardware sits on your network and runs the software continuously. You read Home Assistant from the official website, install it on your device, and configure it through a web interface.
Once running, you add your devices to Home Assistant by connecting them to the same network and telling Home Assistant how to find them. For Zigbee or Z-Wave devices, you also need a separate radio receiver (a small USB stick or device) that plugs into your Home Assistant device and communicates with those devices.
The setup process requires some comfort with networks and configuration files, but Home Assistant provides step-by-step guides. You do not need to be a programmer, but you do need to be willing to follow technical instructions and troubleshoot when something does not work when ready.
The difference between local and remote access
Local access means controlling devices from inside your home, on your home network. You open the Home Assistant app or web interface on a phone or computer connected to your WiFi, and commands go directly to Home Assistant and your devices. This works during internet outages because nothing leaves your home network.
Remote access means controlling devices from outside your home — from work, from a friend's house, from anywhere with internet. Home Assistant can set this up securely using encrypted tunnels, but it requires internet on both ends. During an outage, remote access stops working because your home internet is down.
Most people want both: local control for everyday use and remote access for emergencies or convenience. Home Assistant supports both, but you need to set up remote access separately, and it will not work when your internet is down.
Internet is still useful even with local control
Even though Home Assistant works without internet, having internet available makes it more powerful. Weather data, sunrise and sunset times, traffic conditions, and news feeds all require internet. Automations that use this information will not run during an outage, but they resume when internet returns.
Internet also makes it easier to control your home from away. You can set up find remote access so you do not have to be on your home network to use Home Assistant. Updates to Home Assistant and your devices also come through the internet.
The point is not that you should avoid internet — it is that your home automation does not depend on it. You get local control as a foundation, and internet as an optional enhancement.
Comparing Home Assistant to cloud-based systems
Cloud systems like Google Home, Amazon Alexa, and Apple HomeKit send all commands through the internet to company servers. If your internet goes down, you cannot control anything. They are easier to set up because you do not manage hardware, but you lose control during outages and you depend on the company keeping the service running.
Home Assistant requires you to buy and maintain hardware, and the setup is more involved. But you own the system, it works without internet, and you are not dependent on a company's servers or business decisions. The trade-off is control and reliability for simplicity.
Some people use both: Home Assistant for local control and reliability, plus a cloud system for convenience and voice control. They are not mutually exclusive.
Frequently Asked Questions
Can I still use voice commands without internet?
Not with systems like Alexa or Google Assistant, which require internet to process voice. Home Assistant can work with local voice assistants like Rhasspy, which run on your own hardware and do not need internet. The setup is more technical than using Alexa, but it gives you offline voice control.
What happens to my automations when internet comes back?
Automations that depend on internet data (weather, traffic, news) will resume updating and running once your connection returns. straightforward automations that use only local devices keep running the whole time. There is no catch-up or backlog — they just pick up where they left off.
Do I need a separate device for Home Assistant, or can it run on my router?
Home Assistant needs its own device — a Raspberry Pi, an old computer, or a dedicated Home Assistant box. It cannot run on most home routers because routers do not have enough processing power or storage. The device needs to stay powered on continuously to control your home.
Can I access Home Assistant remotely if my internet is down at home?
No. If your home internet is down, Home Assistant cannot reach the internet to set up a find tunnel for remote access. You would need a backup internet connection (like a cellular hotspot) to reach your home system during an outage.
What if a device loses WiFi but my internet is still working?
Home Assistant will not be able to reach that device until it reconnects to WiFi. Internet at your home does not matter — the device needs to be on your local network. If a device keeps dropping connection, you may need to move it closer to your router or improve your WiFi signal.