Silicon Labs Matter Version 2.9.0-1.6 (June 25, 2026) - Release Notes#

Simplicity SDK Version 2026.6.0

The Silicon Labs Matter v2.9.0-1.6 release provides the functionality to build Matter applications in the Simplicity Studio environment. This release is intended for developers who want to run Matter Demo over Thread (15.4) or Wi-Fi, and also manually build examples through Simplicity Studio v6 / Visual Studio Code or SLC-CLI.

This release is aligned with CSA Matter 1.6 for Thread (MG24, MG26, and MG30) and Wi‑Fi (SiWG917 and MG24 + SiWN917).

Note: At the time of this release, the Connectivity Standards Alliance (CSA) certification is not finalized for Matter 1.6 branch. As a result, this release may not pass all Matter 1.6 certification test cases. If needed, you can either wait for the Matter Extension 2.9.1 patch with the required fixes, or cherry-pick the fixes directly into your branch for earlier adoption. Contact Silicon Labs support if you need any assistance.

Release Summary#

Key Features | API Changes | Bug Fixes | Chip Enablement

Key Features#

  • Quality-tested Matter 1.6 solution for Thread and Wi-Fi.

  • Matter + AWS dual-stack support for 917 NCP boards.

API Changes#

None

Bug Fixes#

See Bug Fixes.

Chip Enablement#

  • Added support for late-arriving refresh boards: BRD4343C for Matter Wi-Fi SoC applications and BRD4357C for selected Matter Wi-Fi NCP applications. Silicon Labs has completed enablement and SQA validation for the supported application scope; customers should refer to the supported boards and application sections for exact coverage.

Key Features#

New Features | Enhancements | Removed Features | Deprecated Features

New Features#

  • Quality-tested Matter 1.6 solution for Thread MG24 / MG26 / MG30, Wi-Fi SiWG917 SoC and SiWN917 NCP mode.

  • Matter + AWS dual-stack support for 917 NCP boards.

  • Added LTO build support for SiWG917 sleepy and non-sleepy Matter Wi-Fi applications

  • Updated the GCC toolchain version to 14.2 release.

Enhancements#

  • Added new reworked Energy Management Clusters.

  • Lighting, Lock, Light Switch, On-Off plug, Thermostat, Rangehood, Platform Template, and Air Quality Apps to support a new appReworked architecture designed to make upgrades easier.

  • Dual IP Stack support for MQTT Sidechannel

Removed Features#

  • Matter Wi-Fi support for MG24 + WF200 has been removed.

Deprecated Features#

None.

API Changes#

New APIs | Modified APIs | Removed APIs | Deprecated APIs

New APIs#

None.

Modified APIs#

None.

Removed APIs#

None.

Deprecated APIs#

None.

Bug Fixes#

ID

Issue Description

GitHub / Salesforce Reference (if any)

Affected Software Variants, Hardware, Modes, Host Interfaces

1571040, 1571039

Fixed CSA test cases TC-RR-1.1 and TC-DESC-2.2 failing when run with the Windows app.

None

All

1563443

Fixed device boot failure for sleepy apps when built with LTO enabled.

None

SiWG917

1545117

Fixed CSA test cases ACE 2.1 and ACE 2.2 failing when run with the test harness.

None

All

1446745

Fixed CSA test cases TC-WNCV failing when run with the Windows app.

None

SiWG917

1563537

Fixed multi-sensor app to read temperature and humidity from the WPK sensor instead of logging identical values.

None

SiWG917

Chip Enablement#

Matter over Thread is supported on the following boards#

  • MG24 boards:

  • MGM24 boards:

    • BRD4316A / SLWSTK6006A / Wireless Start Kit / 2.4GHz@10dBm - xGM240-RB4316A

    • BRD4317A / SLWSTK6006A / Wireless Starter Kit/ 2.4GHz@20dBm - xGM240-RB4317A

    • BRD4318A / SLWSTK6006A / Wireless Starter Kit/ 2.4GHz@20dBm - xGM240-RB4318A

    • BRD4319A (Rev A00 only) / SLWSTK6006A / Wireless Starter Kit/ 2.4GHz@20dBm

    • BRD2704A / Sparkfun Thing Plus MGM240P

    • BRD4337A / SLWSTK6006A / Wireless Starter Kit / 2.4GHz@20dBm - xGM240-RB4337A

  • MG26 boards

    • BRD4116A

    • BRD4117A

    • BRD4118A

    • BRD4120A

    • BRD4121A

    • BRD2608A

    • BRD2709A

  • MGM26 boards

    • BRD4350A

    • BRD4351A

  • MG30 Boards

    • BRD4407A

    • BRD4408A

    • BRD2719A

Matter over Wi-Fi is supported on the following boards#

  • SoC mode:

    • BRD4338A / SiWG917 Wi-Fi 6 and Bluetooth LE 8 MB Flash SoC Pro Kit - SiWx917-PK6031A

    • BRD2605A / SiWG917 Wi-Fi 6 and Bluetooth LE Dev Kit - SiWx917-DK2605A

    • BRD4342A / SiWG917 Wi-Fi 6 and Bluetooth LE 8 MB Flash + 8 MB ext PSRAM Radio Board with an internal RF switch - SiWx91x-RB4342A

    • BRD4343A / SiWG917Y Module Wi-Fi 6 and Bluetooth LE 8MB Flash RF-Pin Radio Board - SiW917Y-RB4343A

    • Early access for BRD4343C / SiWG917Y-X Module Wi-Fi 6 and Bluetooth LE 8MB Flash Antenna Radio Board

    • Early access for new module board BRD2708A / SiW917Y-EK2708A

  • NCP mode:

    • Host Processor:

      • BRD4186C / EFR32xG24 Wireless 2.4 GHz +10 dBm Radio Board (EFR32 radio board) - xG24-RB4186C

      • BRD4187C / EFR32xG24 Wireless 2.4 GHz +20 dBm Radio Board - xG24-RB4187C

    • Silicon Labs Wi-Fi Processor:

      • SiWx917-EB4346A - SiWx917 Wi-Fi 6 and Bluetooth LE Co-processor EXP Expansion Kit

      • SiW917Y-RB4357A - SiWN917Y Module Wi-Fi 6 and Bluetooth LE 4MB Flash RF-Pin Co-Processor Radio Board

      • Early access for SiW917Y-RB4357C Module Wi-Fi 6 and Bluetooth LE 4MB Flash RF-Pin Co-Processor Radio Board

Note: Firmware for SiWN917 NCP, and SiWG917 SoC can be found in the Matter Software Artifacts page in the documentation or Assets section of this page. Connectivity firmware update is mandatory for new release binaries.

Application Example Changes#

New Examples | Modified Examples | Removed Examples | Deprecated Examples

For the list of supported application examples, see Existing Examples. For the details on Matter ecosystems support, see Ecosystems.

New Examples#

  • EVSE

  • Wake on Matter

Modified Examples#

All Matter examples have been renamed to align with the naming convention used across the Simplicity SDK. The new naming format is: Matter <Thread/WiFi> - <SoC/NCP> <Example Name> <OS>.

The following examples have been refactored to support project upgrades from v2.9.0 onward by implementing CRTP architecture. For more information on refactoring effort, see Application Customization Models

  • Lighting

  • Zigbee Matter Light

  • On-Off Plug

  • Thermostat

  • Lock

  • Light Switch

  • Rangehood

  • Platform Template

  • Air Quality Sensor

Removed Examples#

None.

Deprecated Examples#

None.

Known Issues and Limitations#

ID

Issue or Limitation Description

GitHub / Salesforce Reference (if any)

Workaround (if any)

Affected Software Variants, Hardware, Modes, Host Interfaces

The Matter logs are printed to the UART interface by default. To view the logs, use the Simplicity Studio console or a standalone terminal emulator such as PuTTY. The logging destination can be controlled by installing the "Logging To UART" or the "Logging to RTT" component under Matter -> Platform -> Utils in a Matter Studio project.

None

All

The Matter device images require approximately 700 KB in flash space. As a result, only a subset of EFR32MG2x devices are supported. For a complete list of devices supported, see Matter Hardware Requirements.

None

All

On Windows, Matter projects in Simplicity Studio may fail to build due to a known issue with GCC response files and the operating system's command string length limit.

None

When creating a new project, use shorter Solution and Project names and choose a shorter directory path for the project location.

All

A Matter SDK Issue: (https://github.com/project-chip/connectedhomeip). BLE Connection/Timeout error occurs occasionally during commissioning with the chip-tool running on Raspberry Pi or Linux (project-chip#16178). Running on these platforms requires an access point with both 2.4 GHz and 5 GHz capabilities. There is BLE-Wi-Fi interference when connected over the 2.4 GHz channel.

None

This is resolved by connecting the chip-tool device to a 5 GHz SSID and the end device to a 2.4 GHz SSID for the same Wi-Fi network.

All

In some rare cases, a Simplicity Studio project build may fail due to missing files in the zap-generated/ directory (e.g. "gen_config.h not found").

None

Delete the .zap folder in the home directory.

All

1197733, 1228823

Due to an electrical issue on the WPK main boards (BRD4002x), sometimes the current measurement value reported is wrong in the Energy Profiler, making it seem like an ICD is not going to sleep properly even though it is. This issue does not happen when using a WSTK (BRD4001x).

None

All

1416694

The configuration parameters for the internal storage bootloader used in the OTA software updates must always be custom-configured based on the actual image size for the given application. See https://docs.silabs.com/matter/2.9.0/matter-ota/01-ota-bootloader.

None

All

1445664

Chip-Cert executable cannot be used in Windows installations of Simplicity Studio v6.

None

All

Matter/Thread: Silicon Labs has provided a complete image file for the Raspberry Pi that can be flashed onto an SD card to create the Matter Hub, which is a Raspberry Pi running Ubuntu and includes a pre-built version of the Open Thread Border Router (OTBR) and chip-tool. The image we have provided is quite large, (approximately 2 GB). As a result, it can take quite a while to download the .zip file and flash it onto an SD card. Depending on your connection, the process could take up to half an hour. Regardless, the demo and development experiences using this pre-built image are a much faster process than building the Matter Hub from scratch.

None

EFR32

Matter/Thread: Matter attestation credentials can conflict with Lockbits in Series 2, requiring moving the location of the attestation credentials when lockbits are used. See Moving the Matter Attestation Credentials on Series 2 (MG24) for details. (1235425)

None

EFR32

1418676

Possible race condition in UART driver when excessive use of the Matter shell is performed (sending commands every 250 ms).

None

Reduce the command rate.

EFR32

1453646

Level attribute may get incorrectly changed on level-control stop.

None

EFR32

Enabling "Logging to RTT" with SiWG917 SoC results in OTA update failure due to JLink connection preventing soft reset.

None

Enabled UART logging

SiWG917

1366720

BLE scan issues are observed with Raspberry Pi when the distance between the device and the controller exceeds 3 meters in highly congested environment.

None

None

SiWG917

1409219

On the BRD2605A board, RGB LED pins are not configurable via the LED component or Pin Tool, requiring manual updates to the RTE device file for any new LED pin configurations.

None

Hardware limitation.

SiWG917

The external bootloader should not be used with the EFR32MG24+SiWN917 NCP device combination. Only use the internal bootloader.

None

None

SiWN917

SiWN917 NCP application OTA upgrade with upgraded WiSeConnect SDK may not be backward compatible with the existing TA.

None

None

SiWN917

Group commands only work for some specific access points when IGMP snooping is disabled.

None

None

All Wi-Fi boards

When setting up the Ozone Debugger on Mac, the location of the JLinkDevices.xml file has moved. Follow this documentation to place it in the proper location.

None

None

NA

1381843

LCD is disabled on SiWN917 NCP.

None

LCD is disabled.

SiWN917

1563511

Windows app not commissioning with the Apple Ecosystem.

Apple Ecosystem Issue

None

All

1576627

917 sometimes fails to advertise BLE.

None

None

SiWx917

1388334

On SiMG301x boards, the Zigbee Matter Light app may, in rare cases, briefly fail to receive Thread packets. This can lead to OTA update image transfer failures.

None

None

SiMG301x

1617882

SiWx devices fail to commission with the latest updated firmware of amazon ecosystem

None

None

SiWx917

Impact of Release Changes#

Impact Statements | Migration Guide

Impact Statements#

None.

Migration Guide#

sl_main migration: See sl_system to sl_main migration guide for detailed instructions.

Using This Release#

What's in the Release? | Compatible Software | Installation and Use | Help and Feedback

What's in the Release?#

  • Silicon Labs Matter Extension for use with Simplicity Studio and SLC-CLI.

  • Silicon Labs Matter sample applications.

Compatible Software#

Software

Compatible Version or Variant

Simplicity SDK

2026.6.0

WiSeConnect SDK

v4.1.0

GCC (The GNU Compiler Collection)

14.2.1 (provided with Simplicity Studio)

Installation and Use#

To get started, download Simplicity Studio from the following link: https://www.silabs.com/developers/simplicity-studio, and install Simplicity SDK v2026.6.0 along with Silicon Labs Matter v2.9.0. For SiWx917, install WiSeConnect v4.1.0 as well.

Quick-start guides are provided for running pre-compiled demos and for building examples manually.

The Developer's Guide provides information on various technical topics.

For details on Studio project upgrades, see Project Upgrades.

In order to run Matter over Thread, a developer must have a Silicon Labs EFR-based device and either:

  • another EFR-based device and a Raspberry Pi with a 32 GB SD Card,

  • or an ecosystem device with OpenThread Border Router capabilities, such as Amazon Echo, Apple HomePod, Samsung SmartThings Hub or Google Nest Hub Wi-Fi.

In order to run Matter over Wi-Fi, a developer must have the following hardware:

  • Silicon Labs Wireless starter/development kit, which is mentioned below.

  • Raspberry Pi with a 32 GB SD Card or an ecosystem with Matter support

To run your first demo, see our Getting Started Guides.

To kick start your development, see our Developer's Guide.

For information about Secure Vault Integration, see Secure Vault.

To review Security and Software Advisory notifications and manage your notification preferences:

  1. Go to https://community.silabs.com/.

  2. Log in with your account credentials.

  3. Click your profile icon in the upper-right corner of the page.

  4. Select Notifications from the dropdown menu.

  5. In the Notifications section, go to the My Product Notifications tab to review historical Security and Software Advisory notifications.

  6. To manage your preferences, use the Manage Notifications tab to customize which product updates and advisories you receive.

To learn more about the software in this release, see our online documentation.

Help and Feedback#

Note: Ask AI is experimental.

SDK Release and Maintenance Policy#

See our SDK Release and Maintenance Policy.

Additional Information#

Existing Examples#

Matter over Thread is supported in Simplicity Studio for the following applications#

  • Light

  • Light Switch

  • Lock

  • Window Covering

  • Thermostat

  • OnOff Plug

  • Sensor

  • Air Quality Sensor

  • Refrigerator

  • Zigbee/Matter CMP Lighting

  • Closure

  • Fan Control

  • Platform Template

Matter over Wi-Fi is supported in Simplicity Studio for the following applications#

SoC and Dev Kit supported applications:

  • Light

  • Lock

  • Light Switch

  • Window Covering

  • OnOff Plug

  • Thermostat

  • Air Quality Sensor

  • Sensor

  • Fan Control

  • Refrigerator

  • Oven

  • Rangehood

  • Platform Template

  • Closure

NCP supported applications:

  • Lock

  • Thermostat

  • Window Covering

Matter over Wi-Fi ICD is supported for the following applications#

  • Lock (ICD is enabled by default)

    • With EFR32xG24 with SiWN917 in NCP mode

  • Window Covering (ICD is enabled by default)

    • With EFR32xG24 with SiWN917 in NCP mode

  • Thermostat

    • With EFR32xG24 with SiWN917 in NCP mode

  • Light Switch

    • With SiWG917 SoC

Reference guide to enable the sleepy functionality for Wi-Fi: Wi-Fi ICD.

Ecosystems#

This release has been tested and proven to work for commissioning and control with the following Ecosystems on the hardware and software versions listed below:

Google#

Silicon Labs Device

Application

Hub

Phone

App Software

Wi-Fi Access Point

Thread

BRD4187C

lighting/Lock/Window/Multi-sensor-app

Hardware: Google Nest Hub, Model : GUIK2 Software: Hub Software Version: Chromecast 3.78533433

Hardware: Google Pixel 9A Software: Android version 16

Google Home version: 4.18

TPLink Archer AX73

Wi-Fi

BRD4338A

lighting/Lock/Window/Multi-sensor-app

Hardware: Google Nest Hub, Model : GUIK2 Software: Hub Software Version: Chromecast 3.78533433

Hardware: Google Pixel 9A Software: Android version 16

Google Home version: 4.18

TPLink Archer AX73

Apple#

Silicon Labs Device

Application

Hub

Phone

App Software

Wi-Fi Access Point

Thread

BRD4187C

lighting/Lock/Window/Multi-sensor-app

Hardware: Home Pod MiniSoftware: (26.5 (26L471))

Hardware: iPhone 14 pro Software: 26.5

Apple Home 26.5

TPLink Archer AX73

Wi-Fi

BRD4338A

lighting/Lock/Window/Multi-sensor-app

Hardware: Home Pod MiniSoftware: (26.5 (26L471))

Hardware: iPhone 14 pro Software : 26.5

Apple Home 26.5

TPLink Archer AX73

Amazon#

Silicon Labs Device

Application

Hub

Phone

App Software

Wi-Fi Access Point

Thread

BRD4187C

lighting/lock/Window/Multi-sensor-app

Hardware: Echo 4th Gen Model: L4S3RE Software: Hub Software Version:12920396164

Hardware: Google Pixel 9A Software: Android version 16

Alexa version: 2.2.689582.0

TPLink Archer AX73

Wi-Fi

BRD4338A

lighting/lock/Window/Multi-sensor-app

Hardware: Echo 4th Gen Model: L4S3RE Software: Hub Software Version:12920396164

Hardware: Google Pixel 9A Software: Android version 16

Alexa version: 2.2.689582.0

TPLink Archer AX73

Samsung#

Silicon Labs Device

Application

Hub

Phone

App Software

Wi-Fi Access Point

Thread

BRD4187C

lighting/lock/Window/Multi-sensor-app

Hardware: SmartThings Station Software: Hub Software Version: 000.060.00012

Hardware: Google Pixel 9A Software: Android version 16

SmartThings Version: 1.8.45.24

TPLink Archer AX73

Wi-Fi

BRD4338A

lighting/lock/Window/Multi-sensor-app

Hardware: SmartThings Station Software: Hub Software Version: 000.060.00012

Hardware: Google Pixel 9A Software: Android version 16

SmartThings Version: 1.8.45.24

TPLink Archer AX73

Project Upgrades#

Matter 1.6 introduces significant changes. For projects using Matter Extension versions earlier than 2.9.0, do not use Simplicity Studio's automatic project upgrade flow. Instead, follow these steps to upgrade an existing project to Matter Extension 2.9.0 or 2.9.0 to a later version.

  • Create a new 2.9.0 project for the same application type (Lighting, Lock, etc.).

  • For each of the files in the project's src/ and include/ directories that were modified from their original version, apply the corresponding changes to the new project.

  • Replicate the non-default component configurations used in the original project.

  • Using the ZAP tool, replicate the additional cluster configurations applied in the original project.

Matter Software Artifacts#

Matter Software Artifacts: https://docs.silabs.com/matter/2.9.0/matter-prerequisites/matter-artifacts.