Best hardware for a Home Assistant hub

Home Assistant isn't a box you buy off the shelf the way Apple Home or Google Home is. It's software, and you choose what it runs on. That's the whole appeal for a lot of people: you're not locked to one manufacturer's hardware or roadmap. It also means the first real decision in setting one up isn't which sensors to buy, it's what to run it on.

What the hardware actually has to do

A Home Assistant box is really a small, always-on computer. It needs to run continuously, hold a database that grows as automations and sensor history pile up, and (unless you buy an all-in-one) talk to your Zigbee, Z-Wave or Thread devices over a USB radio. None of that needs much grunt for a starter setup. It adds up fast once you're running a camera integration, a big device mesh or several add-ons at once. Compare that with a general-purpose smart home hub: most hubs are closed appliances built for one job. Home Assistant hardware is the opposite: open, and yours to size for what you actually run.

Home Assistant Green, the easy way in

Home Assistant Green is Nabu Casa's own appliance, and it's now the default recommendation for anyone starting out. It's a small, fanless box: a quad-core ARM processor, 4GB of RAM and 32GB of built-in eMMC storage, running completely silently with no moving parts. Plug in Ethernet and power and you're inside the setup wizard in about 15 minutes.

The trade-off is fixed hardware. There's no expansion slot and the 32GB of storage can't be upgraded later, so it's built to be used as-is rather than grown into. It also has no built-in Zigbee, Thread or Z-Wave radio. Despite what you might read elsewhere, Green ships Ethernet-only with two USB-A ports for adding your own dongles, covered below.

Home Assistant Yellow, buy carefully

Home Assistant Yellow was the enthusiast option: a board built around a Raspberry Pi Compute Module 4 that you source and flash yourself, with a Zigbee radio built in (re-flashable to Thread instead, though not both at once) and an optional Power-over-Ethernet kit.

Raspberry Pi, build it yourself

A Raspberry Pi is still the classic way to run Home Assistant, and it's the cheapest path if you already own one. Home Assistant's own install guide asks for a minimum of 2GB RAM, though most people find 4GB or 8GB gives more comfortable headroom once automations, history and a few add-ons pile up.

The one change worth making from the default setup: boot from a USB SSD instead of a microSD card. Home Assistant writes to storage constantly, logging sensor states and history, and microSD cards wear out faster under that kind of continuous load. An SSD costs a little more up front and holds up far better over years of use.

Whichever Pi you use, it has no Zigbee, Thread or Z-Wave radio built in, so budget for a USB dongle on top.

Mini PC or NUC, for heavier setups

If you're running Frigate for local camera AI, a large Zigbee or Z-Wave mesh, or a long list of integrations and add-ons, a small x86 mini PC gives you the CPU and RAM that Green and the Pi don't have room for. Home Assistant's install guide lists a generic x86-64 machine as a fully supported target, not a workaround. N100-class mini PCs are the sweet spot: enough performance for heavy workloads, low power draw for something that runs 24/7, and reliable SSD storage as standard.

Running it as a virtual machine

If you already run a home server or Proxmox box, Home Assistant OS installs as a virtual machine too, officially supported alongside single-board computers. It's worth knowing about, but it's an advanced path: passing a USB Zigbee or Z-Wave dongle through to a VM works, but it isn't automatic, and the device can need reconfiguring if you unplug and replug it. Stick to dedicated hardware unless you're already comfortable running a hypervisor.

The radios you'll need on top

Whichever box you choose (Green, Yellow, a Pi or a mini PC) none of them talk Zigbee, Thread or Z-Wave without extra hardware, except Yellow's single built-in radio. Nabu Casa's own Home Assistant Connect ZBT-2 covers Zigbee and Thread on one USB stick, though not at the same time: each protocol needs its own firmware for reliability. For Z-Wave, the Home Assistant Connect ZWA-2 is the current recommended adapter. One practical tip: plug these into a USB 2.0 port or use a short extension cable. USB 3.0 ports are a known source of 2.4GHz interference for Zigbee and Thread dongles.