Microsoft stack vs open source for South African SMBs. Up to 30 users.
Most small and medium businesses default to Microsoft because it is familiar. But a complete open-source desktop-and-server stack exists today that costs nothing to license. This article compares the two paths using software you can download and install directly — no enterprise agreements, no per-user subscriptions, no minimum seat counts.
The two stacks compared
Direct-download software| Layer | Microsoft path | Open-source path |
|---|---|---|
| Server operating system | Windows Server 2025 Standard 16-core license MSRP ~$1,176/year. Requires CALs for every user or device (~$40–60/user). Datacenter edition ~$6,771/year. |
Ubuntu Server LTS, Rocky Linux or AlmaLinux Free ISO download. Five years of security updates included. No CALs. Optional paid support is available from third parties, but the base OS is $0. |
| Desktop operating system | Windows 11 Pro Retail ~$200–250/device one-off; business volume licensing lowers this. Feature updates delivered by Microsoft. |
Ubuntu Desktop LTS or Linux Mint Free ISO download. Five years of updates, Active Directory join support, Microsoft-compatible fonts. $0. |
| Office productivity | Microsoft 365 Business Standard Desktop + web Office apps, Outlook, 1 TB OneDrive. ~$150/user/year (annual commitment). |
ONLYOFFICE Desktop Editors + ONLYOFFICE Docs (self-hosted) Word, Excel and PowerPoint-compatible editing, offline and in the browser. $0 under AGPL. |
| Files & cloud storage | OneDrive / SharePoint Included in Microsoft 365. 1 TB/user, sync clients for Windows, macOS, mobile. |
Nextcloud Server Self-hosted sync & share with desktop and mobile clients, external sharing, versioning. $0 under AGPL. |
| Team communication | Microsoft Teams Included in Business Standard and above. |
Nextcloud Talk Chat, voice, video and screen share. Runs entirely on your server. $0. |
| Email & calendar | Exchange Online Included in Microsoft 365. Hosted mail, shared calendars, contacts. |
Mailcow or iRedMail on the server + Thunderbird on desktops Self-hosted mail server, webmail and desktop client. $0 community editions. |
| Directory & identity | Microsoft Entra ID / Active Directory Included in Microsoft 365; advanced features require Premium plans. |
FreeIPA or Linux LDAP/AD integration Central login, password policies and single sign-on. $0. |
Note: Prices are public USD list prices or best estimates as of mid-2026 and exclude VAT. Microsoft reseller pricing, Azure Hybrid Benefit and volume discounts can change these figures. The open-source products listed are the free, directly downloadable community editions — support is either community-based or purchased separately from a partner like SciBit.
What it costs a 20-person SMB
License-only estimateBelow is a first-year comparison for a small business with one on-premise server and 20 staff members. Labour, hardware and internet are the same on both sides and are excluded.
Microsoft stack
- Windows Server 2025 Standard 16-core: ~$1,176
- 20 × Windows Server CALs: ~$1,000
- 20 × Microsoft 365 Business Standard: ~$3,000
- Windows 11 Pro device licenses amortised and excluded (one-off ~$4,000 over 5 years)
Open-source stack
- Ubuntu Server + 20 × Ubuntu Desktop or Linux Mint: free
- ONLYOFFICE Desktop Editors + Docs: free
- Nextcloud (files, talk, groupware): free
- Mailcow or iRedMail + Thunderbird: free
- You pay for implementation, migration and ongoing support only
Reality check: The open-source path saves recurring license fees, but it is not zero-cost IT. Someone must install, patch, back up and support it. For an SMB without in-house Linux skills, the smart move is usually to run the open-source stack under a managed services agreement so the savings become real and sustainable.
When each path makes sense for an SMB
No religion, just fitMicrosoft Stay on the Microsoft stack if…
- Your accounting, ERP or design tools only run on Windows.
- Your team is already productive in Windows, Outlook and Excel.
- You prefer one predictable invoice per user per month.
- You rely on complex Excel macros, Power BI or SharePoint workflows.
- You have no appetite for Linux administration or a support partner.
Open Source Consider the open-source stack if…
- You want to eliminate per-user subscriptions as you grow to 30 users.
- Your work is mostly documents, email, file sharing and video calls.
- You want your data on a server you control, in South Africa.
- You have a Linux-capable IT person or a managed-services partner.
- You value being able to inspect, modify or extend the software.
Try the open-source stack directly
Free community editionsUbuntu Server LTS
Enterprise-grade Linux with five years of free security updates.
ubuntu.com/download/server →Linux Mint
A familiar Windows-like desktop that runs well on older hardware.
linuxmint.com/download →Get a comparison for your actual environment
SciBit supports both pathsWe run Microsoft and open-source environments for South African SMBs. Tell us your user count, current apps and data-sovereignty needs and we will return an honest 3-year cost model for each path — including migration, hardware and support.