Home Assistant OS 18: The Update Notes That Actually Matter

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Home Assistant OS 18 had a rough launch. The 18.0 build landed on June 18 2026, then got yanked from the stable channel days later when over-the-air updates started failing on devices with old firmware. The follow-up, 18.1, arrived July 1 2026 and is the version you actually want. If you run Home Assistant on a Raspberry Pi or a Green box, here's what's worth knowing before you tap that update button.

What Shipped

The headline is the kernel jump. HAOS 18 moves from Linux 6.12 to 6.18, the biggest base bump in a while, and it drags Docker up to v29.5.3 alongside a fresh Buildroot. That matters more than it sounds, because newer kernels mean better support for recent USB Zigbee sticks and NVMe drives that gave the 17.x line trouble. Here's the short version of what moved:

• Linux kernel: 6.12 to 6.18, improving USB, NVMe, and newer SoC support
• Docker: bumped to v29.5.3 with containerd v2.2.4
• VM images: now pre-sized to 32 GB, so no manual resize
• Swap: clamped to 1 to 4 GB instead of a flat 33 percent of RAM
• Naming: system services renamed from the hassos- prefix to haos-

None of these are flashy, and that's fine. An operating system update for a device that guards your front door and heating shouldn't be flashy. It should be boring and reliable, which is exactly what a kernel and container-runtime refresh buys you.

Two changes matter most for anyone who reflashes often. The data partition no longer gets over-provisioned, so writing an image to an SD card or SSD is noticeably faster because unused space isn't written at all. And the swap change is smarter than it looks. My Pi 4 with 4 GB of RAM used to hand more than a gig over to swap for no reason, which chewed through SD card write cycles. Clamping it to 1 to 4 GB helps both my little Pi and the folks running Home Assistant on a 32 GB mini PC where a third of the RAM as swap made zero sense.

There's housekeeping too. The old hassos- prefix on system services is now haos-. If you never wrote custom scripts, you'll never notice. If you did, check them.

The Raspberry Pi 5 Catch

This is the part that got 18.0 recalled. On a Pi 5 running bootloader firmware older than 2025-02-12, the display can freeze after the update. Not great when you're staring at a black screen wondering if you just bricked your hub.

Check Your Bootloader First

The good news is HAOS 18 can now update the Pi EEPROM firmware itself. Run the firmware update from the command line, or let the new update entity in Home Assistant Core 2026.7 handle it, then move to the OS update. Do it in that order and the Pi 5 problem disappears. Pi 4 owners get a bonus: new installs switch to the modern KMS graphics driver, which finally turns on HDMI-CEC.

Should You Update?

So is it worth updating? For most people, yes, but skip 18.0 entirely and go straight to 18.1. The kernel bump alone fixes enough hardware quirks to justify it. Just take a backup first, because HAOS doesn't keep a one-click OS rollback, and restoring from a backup is your safety net if something goes sideways.

Here's the honest read on this release. Nothing in it changed how you use Home Assistant day to day. Your dashboards, automations, and integrations all behave exactly as they did on 17.x. What changed is the foundation everything sits on, and that's the kind of update that pays off quietly over the next year as new devices and drivers arrive. Remember the last time an OS update broke your setup right before a busy week? That's why I wait for the point release. HAOS 18.0 got released, stumbled, and was pulled inside a week, which is a decent reminder that being first to a major version rarely wins you anything. Let the early adopters find the sharp edges, then update on 18.1 once the dust settles. If you run anything mission-critical on your hub, like security cameras or door locks, that patience is worth far more than a few days of bragging rights.

If you're still setting things up, our getting started with Home Assistant walkthrough and the Raspberry Pi smart home hub guide both cover fresh 18.1 installs. Deciding between hardware? The Yellow vs Green vs DIY breakdown still holds. Full changelog lives in the official 18.1 release notes.