Unraid vs TrueNAS vs OMV vs Proxmox: NAS OS Pick (2026)

Every NAS thread ends in the same four names, and one of them does not belong. I spent an evening verifying the current state of all four against their own release notes, pricing pages, and documentation, because so much of the standing advice on this comparison describes products that no longer exist, and the details that changed are exactly the ones that decide the purchase: TrueNAS SCALE is gone as a name, TrueNAS CORE is discontinued as a product, Unraid’s “subscription” is not one, and Proxmox, the name that starts half the arguments, does not serve a single network share out of the box and never claimed it could.

Here is the decision, then the evidence.

The short version

Two are free. One is worth paying for. One is a hypervisor wearing a costume.

Mixed drives you already own, apps with minimum friction, money available: Unraid. Uniform drives, integrity as the priority, 8GB of RAM to spare: TrueNAS Community Edition. A weak or small box, Debian comfort, zero budget: openmediavault. And if virtual machines are the actual point of the server, run Proxmox — with a NAS on top of it, not instead of one.

The August 2026 state of play

¹ Official documentation figures; Unraid’s getting-started docs publish no RAM number (only a 4GB USB stick requirement) and its forum moderators suggest 4GB as the practical minimum. ² Subscriptions run €120 (repo access only, no tickets) to €1,100 (unlimited tickets) per socket per year; the free package repo is officially labeled not recommended for production.

What the old comparisons get wrong

The rename nobody indexed. TrueNAS SCALE became TrueNAS Community Edition with 25.04 “Fangtooth” in April 2025, and the FreeBSD-based CORE line is formally finished. The software status page says it is no longer under active development, with 13.0-U6.8 and 13.3-U1.2 as the final builds. Any comparison still weighing “CORE vs SCALE” is a museum piece.

Unraid’s pricing produces the loudest arguments and the most misinformation. The licenses are perpetual. The $36 a year on the Starter and Unleashed tiers is optional and only gates new feature releases; your installed version keeps working and keeps receiving security patches within its minor version. Lime Technology shipped 7.2.8 with a WebGUI CVE fix three weeks after 7.3.2 was already current. Call it a subscription and its forum will correct you, with citations.

RAIDZ expansion stopped being a differentiator. TrueNAS shipped it in 24.10 in October 2024, sponsored by iXsystems, and Unraid’s ZFS pools gained the same one-drive-at-a-time growth in 7.2.0 a year later. The classic “ZFS can’t grow one disk at a time” objection is two years stale against TrueNAS and ten months stale against Unraid.

openmediavault deserves both its reputation and its asterisk. It is the lightest real NAS OS here, it is genuinely free, and the third-party omv-extras mergerfs and SnapRAID plugins recreate Unraid’s mixed-drive economics without the license fee. The asterisk is structural: the GitHub contributor graph shows 8,303 commits by the lead developer against 24 by the next contributor. One maintainer carries the core. OMV 7 also quietly went end-of-life in June 2026, so a fresh install today should start at OMV 8.

The category error

Proxmox VE describes itself as a server management platform for enterprise virtualization. Its storage documentation lists NFS and SMB only as backends it mounts from somewhere else, to hold VM disks and backups. There is no interface anywhere in it for creating a share, and its community answers the recurring question without hedging: “not a NAS software like TrueNAS,” in its own words. That settles it.

So why is it in every NAS thread? Because homelabbers correctly run it as the base layer and put the NAS on top — a TrueNAS or OMV virtual machine with disks passed through, a fileserver LXC, or bare Samba on the underlying Debian. All of those work. None of them makes Proxmox a NAS OS; they make it a hypervisor hosting one, which is a different decision with different failure modes. If that is your situation, the real question is which storage backend to run under Proxmox, and we compare exactly that separately.

Picking by your actual constraint

Your drives are a mixed bag. Unraid’s parity array takes different sizes in one protected pool, and openmediavault reaches the same shape via the third-party omv-extras mergerfs and SnapRAID plugins. TrueNAS will let you mix sizes but charges you for it: ZFS caps every disk in a vdev at the smallest member’s capacity.

Your RAM is tight. TrueNAS officially wants 8GB plus 1GB per drive past eight. OMV officially runs in 1GiB. On a repurposed thin client or an N100 with soldered memory, that spread decides the argument by itself.

You want apps without ceremony. Unraid’s Community Apps store is, in my judgment, the smoothest catalog in home NAS. TrueNAS moved its apps backend from Kubernetes to plain Docker in 24.10, which simplified life, though its forums carry real migration scars from that transition, and the forum threads from the 25.04 virtualization overhaul read the same way. OMV needs the omv-extras compose plugin before Docker exists at all.

Your data is the point and nothing else is. TrueNAS. It is not close, because the whole platform is organized around one job: ZFS end-to-end with checksumming, snapshots, and replication, maintained by a company whose paying enterprise customers keep the storage layer honest whether or not the home users complain loudly enough.

Budget rules everything. OMV and TrueNAS are free. Unraid’s $49 Starter covers six attached devices, which fits most first builds; count your drives before assuming the $109 tier. Run your drive plan through the RAID capacity calculator first — parity overhead changes the real cost per usable terabyte more than the license does.

Whatever wins, put it on hardware that idles politely. A NAS runs 24/7, so the idle-power economics compound annually, and the budget NAS builds and old-PC conversion guide both start from that premise.

Method and limits

Everything above was verified on 2026-08-20 against official release notes, pricing pages, and documentation, with community claims labeled as community claims; the source list below carries the URLs. Two honesty notes from the verification run: the openmediavault docs site blocks automated fetchers, so its facts were checked against the project’s own docs source repository (identical content), and a small number of forum items were verified through search-index snippets rather than full page loads. What this page is not: a hands-on bench of the four installers side by side. I have not run these four concurrently on matched hardware, so you will find no throughput or power numbers here — when we measure that, it will publish as a dataset with the raw files, like our other measured work. Versions move fast in this space; if the table above and a vendor page ever disagree, the vendor page has moved and this page’s lastmod tells you by how much.