What Is Open Source Software?
Open source software is software that's free to use, modify, and distribute. The code is publicly available—anyone can see how it works, improve it, or adapt it for their needs.
This isn't dodgy pirated software. It's legitimate, legal, and often better than paid alternatives.
Some of the world's most important software is open source: Linux runs most of the internet's servers. Android powers most smartphones. Firefox, WordPress, VLC—all open source.
According to the European Commission's 2024 Open Source Study, open source software saves the EU economy an estimated €65-95 billion annually. Small businesses can tap into these same savings.
Why Would Anyone Give Away Software?
It seems counterintuitive. Why would talented developers create software and give it away?
Community development: Many open source projects are built by communities of developers who contribute because they use the software themselves and want it to be better.
Company sponsorship: Large companies like Google, Microsoft, IBM, and Red Hat sponsor open source projects because they benefit from the ecosystem. They make money from support, services, and related products.
Reputation and hiring: Contributing to open source builds reputation and helps developers get hired.
Ideological commitment: Some developers believe software should be free and accessible to everyone.
The result: professional-quality software that costs nothing to use.
The Real Cost Savings
Let's look at actual numbers for a small business with 10 employees:
Microsoft Office 365 Business Standard: £9.40/user/month = £1,128/year
LibreOffice (open source alternative): £0
Adobe Creative Cloud (single app): £19.97/month = £240/year
GIMP + Inkscape (open source alternatives): £0
Microsoft Windows Server: £700+ per licence
Linux (Ubuntu Server, Debian): £0
Jira (project management): From £7.50/user/month = £900/year
OpenProject (open source alternative): £0
Slack paid plan: £6/user/month = £720/year
Mattermost (self-hosted, open source): £0
A small business replacing commercial software with open source alternatives could save £3,000-10,000 annually depending on their software stack.
The Best Open Source Software for Small Business
Office Productivity
LibreOffice (replaces Microsoft Office)
- Word processor, spreadsheet, presentations
- Reads and writes Microsoft formats (.docx, .xlsx, .pptx)
- Works on Windows, Mac, and Linux
- Completely free, no subscriptions
Honest assessment: Very capable for most business needs. Complex Excel macros might not work perfectly. Layout can shift slightly in complex Word documents. But for 90% of office work, it's excellent.
Download: libreoffice.org
Design and Graphics
GIMP (replaces Adobe Photoshop)
- Full-featured image editor
- Supports layers, filters, advanced editing
- Steeper learning curve than Photoshop
- Handles professional work
Inkscape (replaces Adobe Illustrator)
- Vector graphics editor
- Logos, diagrams, illustrations
- SVG native format, exports to many others
Honest assessment: Both are powerful but have different interfaces from Adobe products. If your team already knows Photoshop, there's a learning curve. But for small businesses without existing Adobe skills, these are genuinely good alternatives.
Download: gimp.org, inkscape.org
Email and Communication
Thunderbird (email client)
- Desktop email application
- Works with any email provider
- Calendar integration available
- Free alternative to Outlook desktop app
Mattermost (replaces Slack for self-hosting)
- Team messaging and collaboration
- Self-hosted or cloud options
- Free for self-hosted use
- Very similar to Slack in functionality
Honest assessment: Thunderbird is mature and reliable. Mattermost requires more setup than Slack but gives you full control and zero ongoing cost.
Project and Task Management
OpenProject (replaces Jira, Asana)
- Project planning and tracking
- Gantt charts, agile boards, time tracking
- Self-hosted or cloud options
- Community edition is free
Taiga (replaces Trello, Monday.com)
- Kanban boards and scrum
- Clean, modern interface
- Free self-hosted version
Honest assessment: Both require some technical setup for self-hosting. They're genuine alternatives to expensive project management tools, especially for teams comfortable with a bit of IT work.
Accounting and Finance
GnuCash (basic accounting)
- Double-entry bookkeeping
- Invoicing, reports, bank reconciliation
- Good for simple business accounting
- Completely free
Honest assessment: Less polished than Xero or QuickBooks. No bank feeds (automatic import from your bank). Better suited to businesses comfortable with manual data entry. For very simple needs, it works well.
Customer Relationship Management (CRM)
SuiteCRM (replaces Salesforce)
- Full-featured CRM
- Sales pipeline, contacts, reporting
- Self-hosted and free
- Based on the original SugarCRM code
Odoo (CRM plus more)
- CRM, invoicing, inventory, and more
- Modular—use only what you need
- Community edition is free
- Very capable for growing businesses
Honest assessment: Both require significant setup. SuiteCRM is more traditional CRM. Odoo is broader but more complex. Either can replace expensive commercial CRM for businesses willing to invest setup time.
Server and Infrastructure
Linux (replaces Windows Server)
- Ubuntu Server, Debian, Rocky Linux (replaces CentOS)
- Free operating system for servers
- Powers most of the internet
- Extremely reliable and secure
Proxmox (virtualisation)
- Run multiple virtual servers on one machine
- Free alternative to VMware
- Enterprise features without enterprise prices
Nextcloud (replaces Google Drive/OneDrive)
- Self-hosted file sync and share
- Calendar, contacts, video calls
- Full control over your data
- Free for self-hosting
Honest assessment: Linux servers are standard across the industry. The learning curve is real if you're used to Windows, but documentation is excellent and the community is helpful.
Where Open Source Works Best
Infrastructure and servers: This is where open source dominates. Linux, databases (PostgreSQL, MySQL), web servers (Apache, Nginx)—the entire internet runs on open source infrastructure.
Developer tools: Git, VS Code, programming languages—developers already use primarily open source tools.
Internal tools: Software used inside your business (file sharing, project management, communication) where you control the environment.
Standard tasks: Word processing, spreadsheets, basic design—tasks where the open source tools are mature and well-tested.
Where Open Source Is Harder
Specialist professional software: Accounting software with UK tax integration, industry-specific tools, CAD software—open source alternatives often exist but may lack specific features.
Integration-heavy workflows: If you need tight integration with other paid services, open source tools sometimes don't connect as smoothly.
Support expectations: When things go wrong, you can't call a support line. You're relying on documentation, forums, and community help.
User interface polish: Some open source software is less polished than commercial equivalents. It works, but doesn't look as slick.
The Hidden Costs (Be Realistic)
Open source is free to download. It's not always free to use effectively.
Setup time: Installing and configuring open source software takes time. Someone needs to do it.
Learning curve: Your team may need training on new software. That costs time.
Self-hosting: Many open source tools require you to run your own server. That means hardware, electricity, and maintenance.
Support: When something breaks, you fix it yourself or pay for professional help.
Updates and security: You're responsible for keeping software updated and secure.
For a simple calculation: if a £100/month cloud service saves 10 hours of IT work monthly, it might be the better choice. If it saves 1 hour, open source probably wins.
A Sensible Approach to Adoption
Start with Low-Risk Replacements
Don't switch everything at once. Start with software where the risk is low:
Good starting points:
- LibreOffice alongside Microsoft Office (use it for new documents)
- GIMP for basic image editing (not critical design work initially)
- Thunderbird for email (test with one person first)
- VLC for media playback (replaces Windows Media Player)
Evaluate Properly
Before switching:
1. Identify what you actually use the current software for
2. Check if the open source alternative does those specific things
3. Test thoroughly with real work
4. Get user feedback from your team
5. Have a rollback plan if it doesn't work
Consider Hybrid Approaches
You don't have to choose all open source or all commercial:
- Use LibreOffice for internal documents, Microsoft for client-facing work
- Run open source on servers, commercial software on desktops
- Start new projects on open source, keep existing systems as-is
Budget for Support
Many open source projects offer paid support options. This can be worthwhile:
- Canonical offers Ubuntu support for businesses
- SUSE provides enterprise Linux support
- Many projects have commercial support partners
Paying for support on free software often costs less than licensing commercial alternatives.
Success Stories
Munich city government famously switched 15,000 computers to Linux and LibreOffice, saving millions in licensing costs. They later partially switched back due to compatibility concerns, but many other organisations have made permanent switches.
French Gendarmerie (national police) moved 72,000 computers to Ubuntu Linux and LibreOffice, saving an estimated €50 million over 10 years.
UK Government Digital Service uses open source extensively, including for GOV.UK, and actively promotes open source in public sector procurement.
These are large organisations, but the principles apply to small businesses too.
Making the Decision
Open source makes sense when:
- Software licensing is a significant cost
- You have some technical capability in-house
- You're comfortable learning new tools
- You want control over your systems
- Your needs are well-served by mature open source projects
Commercial software makes sense when:
- You need specific features only commercial tools offer
- Integration with other services is critical
- You need vendor support and guarantees
- Your team strongly prefers familiar tools
- Time is more valuable than money
Getting Started This Week
1. Audit your software spending: List every software subscription and licence. What are you actually paying?
2. Identify candidates: Which software could potentially be replaced? Start with the expensive ones.
3. Research alternatives: Search "open source alternative to [software name]"
4. Test one thing: Pick the most promising candidate. Download it. Test it with real work for a week.
5. Evaluate honestly: Did it work? What was missing? What was better?
6. Decide and act: Either roll out more widely or try the next candidate.
The Bottom Line
Open source software isn't about ideology or being anti-corporate. It's about having options.
For small businesses watching costs carefully, open source offers professional-quality tools at zero licensing cost. The trade-off is typically time and technical capability rather than money.
You don't have to switch everything. Even replacing one or two expensive subscriptions with open source alternatives can save thousands annually.
The software is free. The only cost is your willingness to try something new.
