Unified Multichat: Every Platform's Stream Chat in One Window

What is multichat?

Multichat (also called unified chat, combined chat or multistream chat) is a single view of the live chat from every platform you are streaming to. When you multistream, each platform keeps its own chat: YouTube has live chat, Twitch has chat, Kick has chat and Facebook has comments on the live video. A multichat reads those separate conversations and shows them together, so you are not switching between four browser tabs while you are on camera.

It helps to be clear about what a multichat does not change. Your viewers still see only the chat of the platform they are watching on. A viewer on YouTube does not see messages written on Twitch, and the reverse. The combined view is for you and your team, unless you choose to show it on screen with an overlay (which has a rule on Twitch, covered below).

What Multistream Platform's unified multichat does

Unified multichat is part of the cloud relay. You send one stream from your encoder, the relay delivers it to every destination you enabled, and the chat from the connected platforms comes back into one window. This table lists only what our features, home and pricing pages say about it:

The event audience chat is a different thing from the multichat. Multichat collects the chats that already exist on YouTube, Twitch, Facebook and Kick. The event chat is a chat room inside the player on an event page you host yourself, with its own moderation. If you need a detail that is not on this page, such as a platform not listed here, ask us before you rely on it.

How a multichat works

Every major platform publishes a developer interface for its chat, and a multichat is built on those interfaces. In simple terms:

1. You connect your accounts. Multistream Platform connects social accounts with OAuth, the same sign-in step used to add destinations, so you give permission on the platform itself rather than sharing a password.
2. The service reads each chat. New messages are fetched from each platform's chat interface while you are live.
3. Messages are merged into one feed. A combined feed is only useful if each message shows its author and the platform it came from, so you know where to answer.
4. Replies go back through the platform. Where a platform's interface allows sending messages, a reply is posted into that platform's own chat, which is where its viewers read it.

One practical effect: viewers do not all see your stream at the same moment. Each platform has its own delay, so a question on one platform can arrive a few seconds before or after the same moment on another. When you answer, say the person's name and, if it helps, the platform, so the answer makes sense to everyone. The chat step of our multi-platform guide covers this too.

Twitch's rule on merged chat

If Twitch is one of your destinations, read this before you add any chat overlay. Twitch's Terms of Service (section 11, Simulcasting, last modified August 12, 2026) allow you to stream on Twitch and another service at the same time only if, among other conditions:

• the Twitch experience is no worse than on other services, including your engagement with the Twitch community, for example via chat;
• you do not send your Twitch community to watch the simulcast elsewhere;
• you do not use third-party services that combine activity from other platforms or services on your Twitch stream during the simulcast, such as merging chat.

Twitch's Simulcasting Guidelines FAQ adds that you are free to use tools that combine activity from other platforms, such as chat, for your personal use. In practice that means:

• Reading a combined chat window yourself is fine. It can even help you keep up with Twitch chat, which the rule asks you to engage with.
• Do not show a combined chat on the stream when Twitch is a destination. A relay sends the same picture to every platform, so an overlay in your OBS scene appears on Twitch too. Leave the merged chat overlay out of your scenes for those broadcasts.
• Do not point Twitch viewers elsewhere. Twitch lists chat commands among the ways you must not use to send viewers to another live stream, so keep replies in Twitch chat about the show, not about watching it somewhere else.

Exclusivity agreements with Twitch can override these guidelines. Twitch is the one platform we found with a published rule on merged chat; check the current terms of every platform you stream to. The platform rules section of our multistreaming guide and what is simulcasting cover the rest of Twitch's simulcast rules.

Showing chat on screen with the OBS overlay

The chat overlay is a web page with a transparent background that you add to OBS Studio as a Browser source. The OBS knowledge base describes a Browser source as a web browser inside OBS, and its default Custom CSS makes the page background transparent, which is why only the chat messages appear over your video. To add an overlay:

1. In OBS Studio, select the scene, click + under Sources and choose Browser.
2. Paste the overlay's address into the URL field.
3. Set Width and Height. OBS's default viewport is 800 by 600; choose a size that fits the area of your scene where chat should sit.
4. Leave the default Custom CSS in place so the background stays transparent, then position the source in your scene.

Remember the Twitch rule above: when Twitch is one of your destinations, keep a combined chat overlay out of the scene. When you stream only to platforms without such a rule, an on-screen chat lets viewers on each platform see that you are reading everyone. For the rest of the OBS setup, see how to multistream with OBS Studio and the best OBS settings for streaming.

Moderation stays on each platform

A combined view does not replace each platform's own moderation. Rules, filters and moderators are set per platform, and they keep working whatever tool you read chat in. Set them up before you go live, because a busy multistream gives you less time to react:

Use the strongest filter you are comfortable with on each platform, appoint at least one moderator you trust where the platform allows it, and agree in advance who watches which chat if you have a team. On hosted event pages, the moderated in-player chat room is the one we run, so its moderation happens in Multistream Platform.

How to set up unified multichat

1. Choose a plan on the pricing page. Unified live chat is listed on every plan, including the free Starter plan (marked Basic there).
2. Add your destinations. Connect your accounts with OAuth, or add a platform as a custom RTMP destination with its server URL and stream key (see stream keys by platform). The multichat list covers YouTube, Twitch, Facebook and Kick.
3. Point your encoder at the relay. In OBS Studio, set the service to Custom and paste the ingest URL and stream key; how to multistream with OBS Studio walks through it.
4. Go live once, then open the unified chat window to read and answer messages from every connected platform.
5. Optionally, add the chat overlay to OBS as a browser source, unless Twitch is one of your destinations.

Running a pre-recorded show as live works the same way: viewers still chat on each platform while the video plays. See how to live stream a pre-recorded video.

Tips for managing chat across platforms

• Say the platform when you answer. Viewers on other platforms cannot see the question, so repeat it before you answer it.
• Greet every platform. It is easy to favour the busiest chat. Glance at the smaller ones on purpose, and on Twitch the rules expect it.
• Never paste a stream key into chat. Anyone with your key can stream to your channel. What is a stream key explains how to keep it safe.
• Test before a big show. Run a short private or unlisted test so you can check the chat window, the overlay position and each platform's moderation settings together.
• Use chat replay afterwards. YouTube says live chat replay is available on the archived stream, which helps when you cut highlights or answer questions you missed.

For a full example of a crew running chat on several platforms, see the esports and gaming use case.

Sources

• Twitch Terms of Service, section 11 (Simulcasting), last modified August 12, 2026
• Twitch Help: Simulcasting Guidelines FAQ
• Twitch Developers: Twitch Chat & Chatbots
• Twitch Help: Chat Commands
• Twitch Help: How to Use AutoMod
• YouTube Help: Moderate live chat
• YouTube Live Streaming API: LiveChatMessages
• Meta for Developers: Graph API, Live Video comments
• Kick Help Center: How to moderate your KICK chat
• Kick Help Center: Understanding your KICK Creator Dashboard
• Kick Dev Docs: Chat API
• OBS Studio knowledge base: Browser Source
• Multistream Platform features, pricing and home page (product details)

Platform rules and tools were checked on October 21, 2026. Platforms change their terms and settings, so confirm against the current pages before you go live.