Linux vs Windows Server: which OS should your server run?

Linux and Windows Server can both run a website, a database or a remote service. What decides between them is almost never speed or security in the abstract. It is the software you have to run, the way you want to manage the box, and whether a license fee and a bigger disk are worth it for that software. This guide compares the two on those points with the vendors’ own numbers, and ends with a clear pick for each kind of workload.

Linux vs Windows Server at a glance

No column is highlighted on purpose: for a reader whose software only exists for Windows, the cheaper column is useless. Start from what you will install, then read the sections below.

What each one is best at

Software that needs Windows Server

• .NET Framework applications. Microsoft’s own documentation calls .NET Framework “a Windows-only technology”. Modern .NET (formerly .NET Core) runs on Linux, so an app built on .NET 8 or later can move; an ASP.NET WebForms site or an old WCF service on .NET Framework 4.x cannot without a rewrite.
• IIS-specific sites, Active Directory, Group Policy, Exchange, SharePoint Server and Remote Desktop Services. These are Windows Server roles or products with no Linux edition.
• Desktop programs that have to run around the clock. Trading terminals are the typical case: MetaQuotes documents that MetaTrader 5 “runs on Linux using Wine”, a compatibility layer, while on Windows it runs natively. For Expert Advisors that must keep running after you disconnect, a Windows server is the straightforward route (see running MetaTrader on a VPS).
• Windows-only game servers. ARK: Survival Ascended and Space Engineers ship their dedicated servers for Windows only. Running them on Linux under Wine or Proton works for some people, but it is unsupported by the game developers.
• Automation that clicks through a graphical program, which needs a real Windows session to act in.

Software that is happiest on Linux

• Web stacks: nginx, Apache, PHP, Node.js, Python, WordPress and the databases behind them (MySQL, MariaDB, PostgreSQL, Redis). Every install guide for them starts with a Linux command.
• Docker and Compose. Containers share the host’s kernel, and the images most self-hosted software publishes are Linux images. Windows Server’s built-in container support runs Windows container images. Setting Docker up on Linux takes a few commands: installing Docker on Ubuntu and Debian.
• Bots, VPNs, proxies, monitoring and mail servers. Small services that need no screen run in a few hundred megabytes of RAM on Linux.
• Most game servers. Minecraft, Valheim, Palworld, Rust and Counter-Strike 2 have native Linux server builds.

Things that run on both

Modern .NET, Java, Node.js, Python, Go and PHP run on either. SQL Server is the case people get wrong most often: it has run on Linux since SQL Server 2017, and SQL Server 2025 supports Red Hat Enterprise Linux 9 and 10, Ubuntu 22.04 and 24.04, and Docker on a Linux host. Debian is not on that list, so for SQL Server on Linux pick Ubuntu, and keep Windows for databases that depend on Windows-only features or tools.

How much RAM and disk does each one use?

This is where the two differ most on a small server, and where vendor comparisons tend to say “Linux is lighter” without a number. Here are the numbers each vendor publishes for its own system:

The last two rows are a trap that most comparisons miss. Microsoft warns that installing Windows Server in a virtual machine with only the bare minimum of memory fails. Give the VM 1,280 MB (Windows Server 2025) or 800 MB (2022 and 2019) while setup runs; afterwards Microsoft allows as little as 1,024 MB (2025) or 800 MB (2022 and 2019), depending on the roles you install. For the desktop you log in to over Remote Desktop, keep to the 2 GB minimum or more.

Microsoft adds that 32 GB is enough to install Server Core with the IIS role, and that servers with more than 16 GB of RAM need more disk for the page file and memory dumps. Each monthly cumulative update also stores new versions of system components in the component store (the WinSxS folder). Windows keeps the replaced versions for at least 30 days so an update can be rolled back, then its StartComponentCleanup task removes them, so a Windows disk grows with every update until that cleanup has run. A Linux server’s base system stays within a few gigabytes; old kernels and the package cache take some room (apt autoremove and apt clean free it), and otherwise the disk grows with your data and logs.

Two practical consequences. First, plan Windows on at least 2 GB of RAM before your own software, and on 40 GB of disk or more: 20 GB is below the 32 GB Microsoft names as the absolute minimum and leaves no room for updates. On Standard KVM that means the 40 GB plan or larger for Windows, while the smallest 20 GB plan is plenty for most Linux servers. Second, measure your own server after the first boot and again after a month of updates, because both numbers depend on the image, the roles and the patches installed.

free -h          # "used" and "available" memory
df -h /          # size, used and free space on the root filesystem

Get-CimInstance Win32_OperatingSystem | Select-Object @{n='UsedGB';e={[math]::Round(($_.TotalVisibleMemorySize - $_.FreePhysicalMemory)/1MB,2)}}, @{n='TotalGB';e={[math]::Round($_.TotalVisibleMemorySize/1MB,2)}}
Get-PSDrive C    # Used and Free space on drive C:

TotalVisibleMemorySize and FreePhysicalMemory are reported in kilobytes, so dividing by 1MB (1,048,576 in PowerShell) gives gigabytes.

Is Linux faster than Windows Server?

Not in a way a single number can show, and we have not run a benchmark for this guide. On a small VPS the difference that matters is overhead: every gigabyte of RAM and disk the operating system keeps for itself is a gigabyte your application cannot use. The vendor minimums above put that gap at 1 to 1.5 GB of RAM and close to 30 GB of disk between Debian without a desktop and Windows Server with one, before either runs your software. On a 2 GB server that decides whether a database fits in memory; on a 32 GB dedicated server it hardly shows. Run the commands above after the first boot to see your own figures.

CPU speed depends on the workload, not the OS name. Software runs best on the platform it is built and tuned for: nginx, PHP and PostgreSQL on Linux, IIS and .NET Framework applications on Windows. A Windows program forced onto Linux through Wine, or a Linux container image run on Windows through an extra virtual machine, pays for the translation layer. Pick the platform your software is native to and the performance question mostly answers itself.

Licensing and cost

Debian, Ubuntu, Rocky Linux and AlmaLinux cost nothing to install and update. You can pay for support (Ubuntu Pro beyond its free tier, Red Hat Enterprise Linux), but the server runs fully without it.

Windows Server is licensed per core with a 16-core minimum, plus a client access license (CAL) for each user or device that uses the server. Microsoft’s list prices for Windows Server 2025 are $1,176 for Standard and $6,771 for Datacenter, both for 16 cores; Standard covers two virtual machines, Datacenter unlimited ones. Remote Desktop for more than two people at once needs the Remote Desktop Session Host role and RDS CALs on top: out of the box, Windows Server allows two simultaneous sessions for administration (more than two RDP sessions explains the limit).

Hosting providers handle this in one of three ways: the license is bundled into a higher monthly price, sold as a separate monthly add-on, or not included at all. Ask which one before comparing prices. At VMHeaven, Windows Server 2022 and 2019 can be picked on every KVM plan at the same price as Linux, and no license is included: Windows is installed on Microsoft’s time-limited evaluation license, which runs for 180 days and has to be activated online within the first 10. You can switch to your own retail key at any time by converting the edition with DISM (one restart, no reinstall); a plain slmgr /ipk with a retail key does not work on an evaluation build. slmgr /dlv shows how much evaluation time is left.

Remote access: SSH vs RDP

A Linux server is managed over SSH: a text session on port 22, encrypted, scriptable and light enough to work over a poor mobile connection. Everything, from installing packages to reading logs, happens in that terminal. A Windows server is usually managed over Remote Desktop (RDP, TCP and UDP 3389), which streams the full desktop, or with PowerShell for scripted work.

ssh root@203.0.113.10                # Linux, from any terminal
mstsc /v:203.0.113.10                # Windows Server, from a Windows PC

The lines have blurred. OpenSSH Server has shipped with Windows Server since 2019 as an optional feature, and Windows Server 2025 installs it by default; you only switch it on (Server Manager, Local Server, Remote SSH Access, or Start-Service sshd). In the other direction, a Linux server can offer an RDP desktop through xrdp, at the cost of the memory a desktop needs (setting up xrdp on Ubuntu and Debian).

Whichever you use, expose as little as possible: key-only SSH, possibly on another port (changing the SSH port), or RDP limited to your own IP with Network Level Authentication on (securing RDP on Windows Server). Turning RDP on in the first place is covered in enabling RDP on Windows Server.

Everyday administration side by side

Once you are logged in, the same jobs take different commands. On Windows Server they all run in PowerShell as Administrator, so a Windows admin does not need the desktop for them either:

Security and updates

Neither system is secure or insecure by default; both are attacked constantly, and an unpatched server with a weak password falls on either. The differences are in how the defaults and the update cycle work:

• Attack surface. A minimal Linux install runs few services and no desktop. Windows Server with the Desktop Experience runs more by design; Server Core cuts that down, at the price of the graphical tools many Windows admins rely on.
• Built-in protection. Windows Server ships with Microsoft Defender Antivirus and Windows Firewall switched on. Debian and Ubuntu enable AppArmor, Rocky and AlmaLinux run SELinux in enforcing mode; a firewall such as ufw or nftables is yours to set up.
• Patching rhythm. Windows bundles each month’s fixes into one cumulative update on Patch Tuesday (the second Tuesday), which usually needs a restart. Hotpatch removes most of those restarts for Windows Server 2025 machines connected to Azure Arc, now at no extra cost, but the quarterly baseline months still restart. Linux updates packages one by one as fixes land. A package update restarts its own service, but programs that use an updated library such as OpenSSL or glibc keep running the old code until they are restarted: Ubuntu Server ships needrestart, which does that after each update, and on Debian it is an optional package. Kernel updates need a reboot, and after a glibc update a reboot is the simplest way to be sure nothing still runs the old code.
• Live patching on Linux. The Linux side has its own answer to Hotpatch: Ubuntu Livepatch (part of Ubuntu Pro, free on up to five machines for personal use) and kpatch on Red Hat Enterprise Linux apply kernel security fixes while the server runs. Like Hotpatch, they shorten the list of reboots rather than ending it: a new kernel version still needs one.

sudo apt update && sudo apt install unattended-upgrades
sudo dpkg-reconfigure -plow unattended-upgrades

Get-HotFix | Sort-Object InstalledOn -Descending | Select-Object -First 5

Support length matters as much as patch speed. Windows Server 2022 left mainstream support on October 13, 2026 and gets security updates until October 14, 2031; 2019 until January 9, 2029; 2025 until November 14, 2034. Debian 13 gets security updates from the Debian security team until August 2028 and from Debian LTS until June 30, 2030. Ubuntu 24.04 LTS, the release most VPS images start from, gets five years of standard security support, to May 2029, and with Ubuntu Pro security maintenance to May 2034. Either way, check the date of the version you install, not just the product name.

Moving between them

Switching operating systems is rarely a copy job, but most Windows pieces have a direct Linux counterpart:

• .NET Framework apps have to be ported to .NET 8 or later first; after that they run on Linux like any other .NET app.
• IIS sites move to nginx or Apache. An ASP.NET Core app runs on its own Kestrel server with nginx in front as the reverse proxy.
• SQL Server stays SQL Server: the same engine runs on Ubuntu 22.04 and 24.04, and a database moves across with a normal backup and restore.
• Task Scheduler jobs become cron entries or systemd timers.
• Windows file shares (SMB) are served from Linux with Samba, so Windows clients keep mapping the same kind of network drive.

Going the other way, from Linux to Windows, is mostly a question of whether the software has a Windows build at all; for containers, keep a Linux host.

Pros and cons

Which one should you choose?

Still deciding what kind of server to rent at all? What is a VPS covers the basics, and RDP vs VPS explains what an offer sold as “an RDP” actually is. Windows Server also runs on our bare metal in Amsterdam: see Windows dedicated servers. On the hosting side, Plesk is the panel that covers both systems, while cPanel is Linux-only (cPanel vs Plesk).

Frequently asked