Home Assistant 2026.9: a busy start with Matter, Modbus, and a smarter interface

Home Assistant 2026.9 has arrived for the new school year. And this time, there isn’t any spectacular function that makes you want to redo your entire dashboard in the evening. Instead, the team has tackled a series of small annoyances that can quickly bother us in our daily lives.

Why did this lamp turn on by itself at 3 a.m.? Which USB dongle corresponds to Zigbee? Is my Matter network properly meshed? Is it really the right time to restart Home Assistant when an automation might be running?

Questions I’ve already asked about my own setup. And with Home Assistant 2026.9, some answers are now much easier to find.

There’s also something new on the Modbus side. The name may not sound as exciting as Matter, but for anyone interested in photovoltaics, heat pumps, or energy management, it’s probably one of the most interesting subjects of this version.

Let’s see what this new school year has in store for us.

But why did this light turn on by itself?

This is the kind of situation that those who are starting to have a few dozen automations know well.

A light turns on when it shouldn’t. A shutter closes at a strange hour. A socket just turned off for no apparent reason. We check the history: indeed, the shutter closed at 10:17 p.m. Thanks Home Assistant, but I had noticed that ;-) Now I just need to understand why.

Until now, it often required fishing through automations and consulting their logs. With Home Assistant 2026.9, the activity gives more information about the origin of a change. By expanding an event, you can trace back the chain that led to the action. The shutter was closed by such automation, which itself was triggered by such event.

On a small installation, this is convenient. On a system that has been running for years, with dozens of automations accumulated over time, the time savings can be enormous. I really appreciate this evolution because it addresses a problem that inevitably arises when you push Home Assistant far enough: as you automate the home, you sometimes end up not knowing who controls what!

Not everything is perfect yet. Some manual actions remain difficult to identify precisely. But we already have far more information than before to follow the trail.

Finding information in the history becomes less painful

The History and Activity pages have also been revamped.

A new “Sources” panel serves to filter what is displayed according to the floor, area, device, entity, domain, device class, or integration. Said like that, it seems quite anecdotal. Until the day your Home Assistant counts several hundred entities.

You only want to see the temperatures on the ground floor? The openings on the first floor? All the devices linked to a specific integration? A few clicks are enough. Home Assistant even remembers the selected filters when you return to the page.

The History and Activity sections do not function quite the same way. In History, you must select what you want to display before generating the graphs. Logical: on some installations, trying to trace several hundred entities simultaneously would quickly create a nice mess.

Activity still shows everything by default, and then you refine if necessary.

The period selector has also been redesigned and longer entity names display better.

These are small tweaks. But often, it’s these little tweaks that are most appreciated after a few weeks of use.

The Security dashboard learns to get to the essentials

The Security dashboard gains two functions that I find rather well thought out: favorites and active alerts.

Favorites serve to keep certain devices at the top of the screen. Typically, the front door lock, the garage door, a few cameras or the sensors you check regularly.

Active alerts go a bit further. You choose the important entities, and Home Assistant highlights them when they are in a state that deserves your attention. Two levels are provided: warning and alert. An open window left forgotten could appear as a warning. If the smoke detector triggers, then we clearly move to the higher level. When everything is normal, the section disappears.

I like this philosophy. A security dashboard does not need to show fifty green sensors all the time. What interests me most is what’s wrong.

Matter finally gets its network map

With Zigbee or Z-Wave, you quickly get used to checking the representation of the mesh network to understand how the various devices communicate. Matter can now do the same.

Home Assistant 2026.9 displays the topology of the Matter network as a map. It’s especially interesting for Matter over Thread, as you can see the devices and the Thread border routers present on the network. And that becomes very concrete.

Let’s take a Matter over Thread lock installed quite far away in the house. It regularly loses connection. By looking at the map, we discover that it is a bit isolated in its corner, far from the rest of the mesh. Adding or moving a Thread border router then becomes a pretty obvious lead.

Although Matter was designed to simplify the connected home, once you mix Wi-Fi, Thread, and several border routers, understanding what’s going on under the hood isn’t always evident. This map should help a lot. You just need to use a sufficiently recent version of the Matter server to take advantage of it.

Modbus finally becomes less daunting

Now, we change the subject completely. Modbus is not the protocol you discuss over a drink to impress friends. It dates back to the 1970s, and its operation isn’t particularly glamorous. Yet it’s everywhere.

Photovoltaic inverters, electric meters, heat pumps, ventilation, air conditioning… As soon as you start connecting energy equipment or professional-grade devices to Home Assistant, you inevitably encounter Modbus sooner or later.

Home Assistant has been able to manage it for a long time. The problem is that its configuration often requires getting your hands into YAML, knowing the Modbus registers of the device, their format, and sometimes tinkering with some templates behind. Not exactly the most welcoming part of Home Assistant.

Version 2026.9 begins to change that. Integrations can now directly include the necessary information to communicate with a Modbus device. The idea is for the user to choose their device, and the integration already knows the registers it needs to query. Much cleaner.

Another interesting evolution: Home Assistant can now share the same Modbus connection among several integrations. Imagine multiple devices connected on the same RS-485 bus. If each integration tries to manage its own connection on its own, the troubles are never too far away. Home Assistant can now serve as an intermediary and share this connection properly.

The first integrations are starting to use this new architecture. Fronius can notably utilize Modbus TCP and SunSpec to retrieve more information directly from certain photovoltaic devices.

This is probably the novelty I will follow most closely in the coming versions. Between photovoltaics, residential batteries, charging stations, and heat pumps, Home Assistant is taking an increasingly interesting place in the energy management of the home. And behind many of these devices, Modbus is still present. If their integration becomes almost as easy as adding a Zigbee outlet, we will have come a long way.

MQTT and serial ports organized in one place

As Home Assistant manages new protocols, technical tools have become a bit scattered throughout the interface. Version 2026.9 begins to tidy this up in a section dedicated to connectivity.

MQTT has become much more accessible. Users of Zigbee2MQTT are familiar with these tools: listening to a topic, publishing a message, checking the broker’s configuration… Previously, you had to go into the MQTT integration and then look for the right menu. Now, access is much more direct.

The same goes for serial ports. And having had several USB dongles connected simultaneously to a Home Assistant machine, I can assure you that you quickly end up wondering which corresponds to what. The new panel displays the detected serial ports and the integrations using them. With a Zigbee key, a Z-Wave controller, and an RS-485 adapter plugged into the same machine, that’s far from superfluous.

Tile cards continue to replace old maps

Tile cards have evolved a lot in recent years, and I am using them more and more in my own dashboards. Home Assistant 2026.9 adds three new commands to them.

For compatible lights, you can now directly choose a light effect. This is particularly handy with WLED, where the list of effects can quickly become… endless. Fortunately, you can select only the ones you really use.

Robot vacuums gain a direct suction power adjustment. Again, you can choose the levels to display.

Compatible Climate devices can propose the target humidity adjustment.

And there’s another small modification that visually changes quite a bit: multiple functions can be placed on the same line in a tile card. Thus, the dashboards can remain compact while providing access to more commands.

Home Assistant makes its graphs accessible to visually impaired people

This new feature will probably go unnoticed by many users. However, it deserves a moment of attention. Home Assistant graphs can now be navigated using the keyboard and read by screen readers.

Until now, a graph essentially remained a visual element. For a visually impaired person, retrieving the precise data it contains was not easy. The various points can now be navigated with the keyboard.

Home Assistant goes even further with an audio system: the tone changes depending on whether the curve rises or falls. In other words, you can literally listen to the evolution of a graph.

I think the idea is quite brilliant. It’s typically the kind of improvement that some users will never notice, while it can completely change the experience for others.

How much space is left on the NAS?

Home Assistant knows how to use a NAS or other network storage, particularly to send its backups there. Curiously, there was still quite a basic piece of information missing: how much space is left? That’s fixed now. Go to Settings > System > Storage. Home Assistant now displays the occupied space and the available space on the configured network locations. This avoids opening the NAS interface just to check that a backup isn’t going to fill up the disk.

Not exactly headline news, of course. But I really like this kind of improvement.

The maps switch to OpenStreetMap vector data

The mapping system is also changing in Home Assistant 2026.9.

Home Assistant used to use raster tiles, meaning small images assembled to form the map. The new version uses vector data from OpenStreetMap. The change was accelerated by an issue with the previous map provider, but the team took the opportunity to revamp the system.

Maps now remain sharp during zooming, and this technology allows for more freedom for the future: themes, dark mode, different languages, or styles suited for certain uses. The choice of OpenStreetMap fits quite well with Home Assistant.

There’s even a nice little aspect: if the road in front of your house does not exist or is inaccurately reported, you can correct it in OpenStreetMap. Once the change is propagated, it will also arrive in Home Assistant.

Home Assistant Cloud strengthens security

There are also changes for Home Assistant Cloud subscribers.

Remote connections now properly transmit their original IP address to Home Assistant.

Why is this interesting? Because some connections could previously appear as coming from 127.0.0.1, that is, from the Home Assistant machine itself. Not very practical when trying to ban an IP address after several incorrect connection attempts.

The banning mechanism can now work properly with connections coming through Home Assistant Cloud.

Home Assistant is also testing a new voice recognition engine provided by Soniox in Labs. It aims for better recognition of accents, noisy environments, and languages other than English. For us Francophones, it definitely deserves a little test. The feature remains experimental and must be activated in Settings > System > Labs.

Even more possibilities around the sun

Automations related to the sun are no longer limited to the classic sunrise/sunset. Home Assistant adds events related to the golden hour, blue hour, and even polar sun.

The blue hour, for example, can be interesting for gradually triggering outdoor lighting instead of just waiting for sunset.

I already use sunrise and sunset times a lot in my automations, particularly for shutters. Having additional markers offers some interesting possibilities for managing lighting more finely according to natural light.

Home Assistant warns you before restarting at a bad time

This is a situation that has happened to me before. You change something, Home Assistant requests a restart, you click… and then you realize afterwards that a script or an automation was just running. Home Assistant 2026.9 now checks this point.

When it’s time to restart, the confirmation window displays the automations and scripts that are still running. It’s up to you to wait for them to finish before restarting the system.

It’s just one more line in a window. But it can prevent some rather strange behaviors in the house.

And lots of little things here and there

As often with Home Assistant updates, the full changelog is much longer than the few highlighted new features.

The Energy dashboard, for example, displays the names of devices more clearly. Handy when several curves simply call themselves “Energy,” which happens more often than we would like.

Dashboards also gain a background adjustment directly from the interface. No more need to go through YAML for this part.

Templates now accept more custom attributes. Some shutters can expose their speed. The media search can query more compatible libraries.

Thirteen new integrations also appear with this version.

Users of Proxmox can even pause a virtual machine from Home Assistant. For a homelab, there are probably some interesting scenarios to imagine. Why let certain VMs run all day if no one needs them?

An update that mainly makes Home Assistant easier to live with

After going through all the new features of version 2026.9, it’s ultimately the diagnostic improvements that stand out the most to me.

Home Assistant has become extremely powerful. For some of us, it now controls hundreds of entities, dozens of automations, and several protocols. And the more things we add, the more a simple question becomes complicated: “Why did the house just do that?”

Being able to easily trace back the origin of an action will thus be much more useful to me than a new animation in a dashboard.

The same observation applies to the Matter map, the identification of serial ports, or the warning before restart. These are tools that we don’t necessarily need every day. But the day something doesn’t work, we’re glad to have them.

I’m also keeping a close eye on Modbus. Home Assistant is increasingly interested in energy, and this protocol remains very present in photovoltaics, heating, and professional equipment. Making it more accessible can unlock a lot of things in the coming months.

So Home Assistant 2026.9 is quite a discreet update at first glance. After a few minutes of digging into it, it ultimately reveals many small improvements that are likely to be adopted very quickly.

As usual, there’s the customary rule before clicking “Update”: a quick look at the incompatible changes to check your integrations and then a complete backup of Home Assistant.

It takes five minutes. And the day an update goes wrong, those five minutes suddenly seem very well invested ;-)