I've encountered this issue again with version 6000.3.11f1.
My project uses ~3GB (in the first few minutes), and after a while, it goes up to 5GB, then 8GB, 12GB, and so on, until my RAM is full and the editor crashes.
When I close and reopen Unity, the free memory is restored.

Please fix this issue

This is still happening in the "fixed" 6000.3.11f1 version as of 3/17/2026.
I've submitted a bug report for it. I can't access the bug report for some reason, but it's worded similar to this post. The only stipulation is that for me at least, I can generate 50-200 mb of RAM usage just by reloading the domain. Literally just a space added to an empty script file, reload domain and boom +200mb. Sometimes it's even a whole gig added. This is freaking insane.

Is this something that affects 6000.0.66+ much? Unity's "Package Manager error resolved, new Hub badge warning" post recommends upgrading, but I'd rather have a Package Manager issue than a massive permanent memory leak.

You can add Linux in!
Im on Fedora 43 and i was having nightmares with this. At first i thought it was linux version, but im reading its not even listed here!

I tried both with an existing project and a new empty URP scene. The memory leak is WILD.
It simply has made the engine unusable at this point.

Please fix it asap!

I confirm, this is a bug that needs to be fixed first. When I launch my project, the editor only takes up 3.2 GB, but after a while it takes up more and more space until the memory is full and, it crashes !
I use the particle system, the Splines package, Visual Studio, Shader Graph, ProBuilder, and mesh models for a small 3D project.

It's urgent to have a functional 6000.X version... Many thanks when you have fixed the problem.

This issue is absolutely unacceptable for a production‑ready engine.
Unity 6000.x is literally unusable due to this memory leak.
I am experiencing 20–25 GB of RAM usage in a completely empty URP project, even without entering Play Mode, without the Profiler open, and even after switching to DX11. The Editor keeps allocating memory endlessly until the entire system becomes unstable.
This is not a minor inconvenience.
This is a critical Editor‑level failure that makes Unity 6 impossible to use for real work.
The fact that this issue has been reproducible for months, across multiple 6000.x versions, and still remains unfixed is extremely concerning. Unity advertises 6000.x as a stable release stream, yet the Editor cannot even remain open without consuming absurd amounts of memory.
Please prioritize this immediately.
A modern engine cannot ship with a memory leak that triggers in a blank project.
This should be treated as a blocker, not a low‑priority item.
Unity users deserve a functional Editor, not a tool that eats 20+ GB of RAM doing nothing.

I think this is not only happening when enter-exit play mode. We have memory leak problem in two different project (6000.0.66f1, 6000.3.5f2). Unity can easily use 20-40 GB (yeah, GB) memory when I check from the Activity Memory. We're periodically reopening Unity because of this problem.