Specification | Matter Handbook

The Matter specification is the technical foundation of the Matter protocol. There are normally two minor releases per year, in Spring and Fall, with optional follow-up patch releases between the minor releases.

Latest Release

Version 1.5.1 (March 2026)

All specification documents are available for download from the Alliance website.

Download Specification

What's New in 1.5.1

Building on the camera and video doorbell support introduced in 1.5, this maintenance release focuses on streaming efficiency, media capabilities, and device refinements:

Multi-stream video - Cameras can now deliver multiple optimized streams simultaneously (e.g. high-res for recording, low-res for mobile, and a separate stream for AI processing), reducing bandwidth overhead.
HEIC snapshots & CMAF streaming - Snapshot images can use the HEIC codec for better quality at smaller file sizes. Recorded video gains HLS/DASH upload support via the CMAF Interface-2 profile.
Pan-tilt-zoom improvements - Greater flexibility for camera positioning, including better support for installations where the home position is at the edge of the rotation range.
Chime & intercom updates - Controllers can now request a specific chime sound rather than only the default, enabling per-doorbell or contextual chimes. Intercom devices gain clearer signaling requirements and integrated chime support.
Bug fixes & clarifications - Recording configuration validation, doorbell stability improvements, and editorial refinements across the camera-related specifications.

Read the full announcement

https://csa-iot.org/newsroom/matter-1-5-1-enhancing-camera-performance-and-expanding-device-flexibility/

Alliance Members

In-progress drafts of the specification are available through the Secure Document Access Portal (requires Alliance member login).

Members actively contributing to specification development may submit and review content in the Specification GitHub Repository. If you are a Participant or Promoter member and need contributor access, please email help@csa-iot.org.

Specification Documents

The specification is made up of four documents:

Document	Description
Core	Defines the foundational components of Matter, how they interact, and the common procedures that underpin the protocol.
Application Cluster	Details the data models for each cluster that makes up an endpoint, describing their attributes, commands, and events.
Device Library	Sets out the types of end-user devices in Matter and specifies which application clusters each device type requires.
Namespace	Defines common data formats and structures shared across multiple clusters. Introduced in version 1.2.

Release History

The Alliance aims to publish two releases per year. The specification follows a major.minor.patch versioning scheme:

Minor releases (e.g. 1.3, 1.4, 1.5) introduce new device types, clusters, and protocol features.
Patch releases (e.g. 1.4.1, 1.5.1) primarily contain corrections and clarifications, but may also include smaller new features.

Version	Published	Highlights
1.5.1 Latest	March 2026	Multi-stream video, HEIC/CMAF media
1.5	November 2025	Cameras, closures, soil sensors, energy tariffs, TCP transport
1.4.2	August 2025	Wi-Fi-only commissioning, security enhancements, certifiable scenes
1.4.1	May 2025	Enhanced Setup Flow, NFC onboarding, multi-device QR code
1.4	November 2024	Enhanced Multi-Admin, network infrastructure, solar, batteries, heat pumps
1.3	May 2024	Energy reporting, EV charging, water management, kitchen appliances, scenes
1.2	October 2023	Vacuums, appliances, smoke/CO alarms, air quality, fans, Namespace Spec
1.1	May 2023	Intermittently Connected Devices (ICD)
1.0 Initial Release	November 2022	Lighting, plugs, locks, thermostats, blinds, sensors, media

Last updated on 2026-04-08