How to Read Your Thread Network Map in Home Assistant
Smart Home•Nov 2, 2026•8 Min Read
Home Assistant can now draw your Thread network as a map. Here is how to open it, what every dot and line means, and how to spot a network that needs one more smart plug, using an example home with seven roller shades.
The post office, on a map
In How Matter over Thread works we described a Thread network as a postal service. Your command is a letter. A post office takes it in from your Wi-Fi. Carriers, which are always-on devices like smart plugs, move it along. Your shades sleep, so each one keeps a mailbox at a nearby carrier and checks it on a schedule.
Until recently you had to take that picture on trust. Since September 2026, Home Assistant draws it for you: your Matter devices and border routers, who they talk to, and how strong each connection is. Thread devices it doesn't manage can still appear, as unknown dots.
This guide reads that map on an example home: seven roller shades, a door lock, two Thread remotes, three smart plugs, and an air quality monitor that has gone offline.
Opening the map
In Home Assistant, go to Settings → Connectivity → Matter. Under My network, select Show map.
You need Home Assistant 2026.9 or newer, the Matter Server app at version 9.2.0 or newer, and an administrator account.
The map updates itself as your network changes. There is a Refresh topology button, but it asks every device for a fresh report at once, so use it only when you need to. If the map says "No network topology data is available yet", Home Assistant hasn't received those reports from your devices yet.
The dots: who’s who
Home Assistant gives each kind of device its own shape and color. Here is what each one is, in the language of the post.
Home AssistantBlue square. Where your letters start.The center of the map. Every command from your phone or an automation leaves from here.
Border routerPurple square. The post office.The device on the border between your home network and Thread, where every letter crosses over.
RouterLight blue circle. A carrier.An always-on device that passes mail on for others. One router has an extra outline: the Leader.
End deviceTeal circle. A household.A device that gets mail but never carries it. Your shades are here.
OfflineRed circle.Home Assistant can’t reach it right now.
Unknown deviceGray circle.A Thread device your devices can hear but Home Assistant doesn’t manage, such as another brand’s border router.
Device types, in plain words
The map sorts devices into routers and end devices. Open a device's page in Home Assistant and you will meet a few more names. They all answer the same two questions: is the radio always on, and does it carry mail for anyone else?
What each label means
| You’ll see | What it means | In the example home |
|---|---|---|
| Sleepy end device | Radio off most of the time. Wakes on a schedule to check its mailbox. Never carries for anyone. This is what you want from anything on a battery. | All seven rollers, the door lock and both remotes |
| End device | Radio always on, but it still only receives. It never carries mail for others. | None |
| Routing end device | Home Assistant’s name for an always-on device that can carry mail. Whether it is carrying right now is up to the network. | The three smart plugs |
| Router-eligible | Able to carry, but the network hasn’t needed it yet. The network promotes it through the Leader, with nothing for you to do. | None right now |
| Leader | One router the network elects to run things, such as deciding which devices become carriers. If it disappears, another router takes over. | The Bedroom 1 plug |
| Border router | A job, not a type: the post office between Thread and your home network. It carries mail too. | A Home Assistant Connect ZBT-2 stick |
Two things that follow
Every Thread device joins as an end device and can be promoted later, so a new plug may not start carrying right away. And the Leader doesn't have to be the border router. In the example home, a smart plug is in charge.
You may also see orange lines. Those are Matter devices on Wi-Fi, which share the map but not the post. The outdoor plug in the example is one: it shows up, but it carries nothing for the shades. If you buy a plug to extend Thread, check that it says Thread, not just Matter.
The example home, read aloud
One post office. Everything enters Thread through a single border router, a Connect ZBT-2 USB stick plugged into Home Assistant.
Every carrier can reach every other one. Four always-on devices make six connections, and all six are strong. This is what a healthy small network looks like. If one connection fails, the Thread standard has carriers pick the next best route on their own.
Every sleeping device has exactly one mailbox. The living room plug holds mail for the three living room rollers and the door lock. The Bedroom 2 plug holds it for the two bedroom 2 rollers. The Bedroom 1 plug holds it for the two bedroom 1 rollers and both remotes.
Rooms mean nothing to Thread. Here every roller uses the plug in its own room, but that comes from distance, not names. The rooms you set in Home Assistant are labels for you; the network never sees them. A shade can just as well keep its mailbox at the plug in the next room.
One device is down. The air quality monitor is offline, so Home Assistant shows it in red, with a dashed line to the plug it was last connected to.
Reading the lines
Purple is a Thread connection. Orange is Wi-Fi.
Thicker means a stronger signal. Select a line to see Strong, Medium, Weak or Unknown, plus the numbers behind it.
Dashed means the signal was only seen in one direction, or is different each way. Lines to an offline or unknown device are dashed too. An arrow shows which way.
Dotted means the connection is only known from a router's list of routes, not from a direct check. A connection with no recent signal isn't drawn at all.
The numbers come in two kinds. Link quality runs from 0 to 3: 3 is good, 0 means no usable link. Signal strength is a negative number in dBm, and closer to zero is stronger. Every link in the example home scores 3. The door lock reads −27 dBm from its plug. The weakest carrier link, between the border router and the Bedroom 1 plug, reads −74 dBm and is still rated strong.
Five things to look for
Red dots. Something is offline, like the air quality monitor in the example. Check that it still has power (for a battery device, the battery), then whether it still has an always-on device nearby.
Thin lines to your shades. The shade is at the edge of its carrier's reach. A Thread smart plug halfway between them fixes it.
One carrier holding every mailbox. Each always-on device can only hold so many. Spread a few around the house.
A single post office. The example home has one, and for a home this size that is fine. Just know that if it loses power, app and voice control stop until it's back. The Thread Group warns about exactly this. Yamazing remotes use their own radio, so the shades still move. In a larger home, a second border router is cheap insurance.
Gray dots. Thread devices Home Assistant doesn't manage, often another app's border router, like a HomePod or Nest Hub. Home Assistant notes the same border router can show up twice. Nothing to fix.
One last thing: the map is a snapshot. Thread rearranges itself all the time. A shade can move its mailbox, a plug can be promoted. If something looks odd, check again later before you change anything.
Frequently asked questions
Sources
Opening the map, its requirements, symbols, line styles and the device-type labels come from Home Assistant's Matter integration documentation and the 2026.9 release notes, with background in The Matter upgrade you've been waiting for.
Device roles, the Leader, promotion of router-eligible devices, joining as an end device, self-healing routes, the 0 to 3 link-quality scale and the single-border-router warning come from the Thread Group's Thread Network Fundamentals.
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