How to Multistream to Twitch and YouTube at the Same Time

Your audience is split. Some viewers only open Twitch, others only watch on YouTube, and picking one platform means leaving half of them behind every time you go live. The obvious fix is to multistream to Twitch and YouTube at the same time, but doing it badly costs you picture quality, dropped frames and a chat you cannot keep up with.

I have set up simultaneous broadcasts for a weekly podcast, two music shows and a handful of charity streams. Here is what actually works, what each method costs in bandwidth and money, and where the usual advice misses.

Three ways to multistream to Twitch and YouTube

There are only three practical routes, and the right one depends mostly on your upload speed and how much your computer can handle.

Method	Upload needed	Extra CPU or GPU load	Cost
Cloud relay service	One stream, about 6 to 8 Mbps	None	Free tier or roughly $16 to $40 a month
OBS multi-output plugin	Two streams, about 12 to 16 Mbps	None if both outputs share one encode	Free
Two separate encodes	Two streams at different settings	Roughly double	Free

A cloud relay takes one stream from your computer and copies it to every platform from its own servers. Your upload only carries one feed, which is why it suits home connections. The trade-off is a monthly fee for higher resolutions and one more service between you and your viewers.

The plugin route sends separate streams straight from OBS. You need enough upload to carry both, so measure before committing. If you have not done that yet, the guide on stream bitrate settings that match your upload speed walks through the test and the 75 percent rule I still use.

Setting up the OBS plugin method step by step

This is the method I recommend for anyone with at least 20 Mbps of steady upload, because it is free and you keep control of each output.

Install the Multiple RTMP Outputs plugin for your OBS version, then restart OBS. A new dock appears, usually labeled Multiple Output.
Set your main output in Settings, Stream, to Twitch with your stream key. This is the feed the normal Start Streaming button controls.
In the new dock, click Add new target. Name it YouTube, paste the RTMP server address and stream key from YouTube Studio, and choose to share the encoder with the main output.
Set the main encoder to 1080p at 60 frames per second around 6,000 Kbps, or 720p60 at 4,500 Kbps if your upload is tighter. Keyframe interval at 2 seconds keeps both platforms happy.
Start the main stream, then click Start on the YouTube target. Check both dashboards for a healthy status before you speak.

Sharing one encode is the key detail. It means your graphics card only does the work once, and the second stream adds network load but almost no processing load.

When two encodes make sense

Twitch caps most channels at around 6,000 Kbps, while YouTube happily takes 9,000 Kbps or more at 1080p. If you have the upload and a modern GPU encoder, a second encode lets you send YouTube a sharper picture. On an NVIDIA card with NVENC, two 1080p encodes typically add 5 to 10 percent GPU load. On a CPU encoder with x264, it can push an older processor into dropped frames, so test for 30 minutes before a real show.

Rules and settings to check before you go live

Platform rules change, so read the current terms on the day you set this up. As of recent policy, Twitch allows simulcasting to other livestream services for most creators, but it still expects the Twitch experience to be as good as anywhere else. That means do not send Twitch a worse picture than YouTube, and do not post a banner telling viewers to leave for another site.

A few other settings catch people out:

Titles and categories. Each platform has its own title and category. Set both before you go live, because changing them mid-stream on two dashboards is fiddly.
Latency. YouTube's low latency mode lands around 3 to 5 seconds of delay. Twitch is often 2 to 4 seconds. Viewers will notice when you answer a question a few seconds late on one side.
Audio tracks. If you mute copyrighted music on one platform's VOD track, that setting usually does not follow the second output. Check what each platform records.
Reconnect behavior. Turn on automatic reconnect in OBS advanced settings so a short drop does not end one of the two streams for good.

Why a single combined chat is not always the answer

The standard advice is to merge chats from both platforms into one overlay so you never miss a message. I used to recommend it without thinking. I now treat it as optional, and sometimes harmful.

A merged overlay shows Twitch viewers what YouTube viewers are saying and the other way round, but neither group can reply to the other. That creates one-sided conversations, people repeating questions, and occasionally a viewer on one side getting piled on by someone they cannot answer. On a small show with under 50 concurrent viewers, I find it is cleaner to keep a merged chat window for yourself only, off screen, and read messages aloud with the platform name. Viewers on both sides hear the full conversation and nobody feels ignored.

On bigger shows, the honest fix is a moderator on each platform, not a clever overlay.

Testing your multistream before a real show

Run a private or unlisted test on both platforms for at least 20 minutes. YouTube lets you set a stream to unlisted. Twitch has a bandwidth test mode through some tools, or you can stream at a quiet hour with a placeholder title. Watch for these numbers in the OBS stats panel:

Dropped frames due to network under 0.5 percent on each output.
Frames missed due to rendering lag at zero.
Encoding lag under 1 percent.

If network drops climb on only one output, the problem is usually the route to that platform's ingest server, so try a closer server. If drops climb on both, lower the bitrate by 500 Kbps at a time. A wired connection is close to mandatory here, and the guide to setting up a stream that survives a bad internet day covers the backups worth adding.

Frequently asked questions

Is it allowed to stream on Twitch and YouTube at the same time?

For most creators it currently is. Twitch updated its rules to permit simulcasting to other livestream services, with conditions about keeping the Twitch experience equal in quality. Always check the latest terms for your account type before you start.

How much upload speed do I need to multistream?

With a cloud relay, the same as a single stream, around 8 to 10 Mbps for 1080p60. Sending two streams directly from OBS needs roughly double, so plan for 20 Mbps or more of stable upload to keep a safe margin.

Does multistreaming lower my stream quality?

Not if you share one encode and have enough upload. Quality drops when your connection is overloaded or your computer runs two heavy encodes. Test for dropped frames first, and lower the bitrate before you lower the resolution.