# Open-Source Alternatives to the Business Software You Pay For (2026)

> **Quick answer:** Yes, there are mature free equivalents for scheduling (Cal.com), CRM (Twenty), customer support (Chatwoot) and document signing (Documenso). All are free to licence and all need a server costing around $12/mo plus someone to maintain them. **They pay off if you’re billed per user and have a team**, or if your data shouldn’t leave the building. If you’re one or two people paying €30 a month, switching loses you money in time.
 

When the monthly software bill starts to hurt, the question appears: isn’t there something free that does this? The honest answer is that there is, that it’s better than people expect, and that **it isn’t entirely free**. Here are the real alternatives by tool type, what they actually save you, and the point at which this stops being a good idea. 

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## The table, by what you need to solve
 

| You need | Open-source option | Replaces | RAM | Difficulty |
| --- | --- | --- | --- | --- |
| Scheduling and online booking | **Cal.com** | Calendly, commission-based booking platforms | 2 GB | Medium |
| Customer CRM | **Twenty** | Pipedrive, HubSpot | 4 GB | Medium |
| Customer support (chat, WhatsApp, email) | **Chatwoot** | Intercom, Zendesk | 4 GB | Medium |
| Electronic document signing | **Documenso** | DocuSign, Signaturit | 2 GB | Medium |
| Product or web analytics | **PostHog** | Mixpanel, Amplitude | 8 GB | High |

 

*Memory figures are indicative, for small-business usage. Every project in the table was active as of 6 September 2026; the current status of each is in the [project directory](/en/tools/ai-directory/).* 

## Where each one fits, by sector
 

**Cal.com, if your business lives on the calendar.** Clinics, salons, physiotherapy practices, veterinary surgeries. The point isn’t only saving the subscription: it’s that the booking happens on your own domain and the patient is yours, not a platform’s — one that also takes a commission per appointment and resells them back to you. If you’re weighing paid options, we have comparisons for [salon software](/en/best-salon-software-2026/) and [dental clinics](/en/dental-software-spain-guide/). 

**Twenty, if per-user CRM pricing is getting away from you.** The per-user model hurts most as the team grows: going from 3 to 8 salespeople multiplies the bill. Twenty is younger than the commercial CRMs and it shows in the details, but it covers the basic contacts-and-deals flow. Compare it against what’s out there in [best real-estate CRM](/en/best-real-estate-crm-spain/). 

**Chatwoot, if you support across several channels.** It merges website chat, WhatsApp and email into one shared inbox. It replaces tools that charge per agent, so the saving scales with team size: for one person it isn’t worth it, for five it becomes real money. 

**Documenso, if you sign documents daily.** Law firms, estate agencies, contractors with quotes that get signed. Commercial platforms charge per envelope sent and that adds up fast. It connects with our comparison of [law practice management software](/en/law-practice-software-spain/). 

## What it actually costs
 

The licence is €0. The rest isn’t: 
- **The server**: from around $6.49/mo in year one, **$11.99 on renewal**, for the 4 GB plan at [Hostinger](https://tumetodosaas.com/go/hostinger). You can run several of these on one machine if you add up their memory and don’t overreach. Plan breakdown in [which VPS you need](/en/best-vps-for-n8n-2026/).
- **Installation**: an afternoon per tool if servers aren’t your world.
- **Maintenance**: updates, certificates and backups, every month, forever.
 

That third point is what decides it. We work through the numbers in [is it worth it for a small business?](/en/is-self-hosted-n8n-worth-it-small-business/), and the conclusion is the same here: **the saving is only real when the subscription you drop is large**, which usually means per-user pricing with a team behind it. 

👉 [See server plans for self-hosting](https://tumetodosaas.com/go/hostinger) 

## When NOT to switch
 

Let’s be blunt, because this is the advice most likely to save you money: 
- **If you’re one or two people** paying €20-40 a month in total. The time to set up and maintain is worth more than that.
- **If your paid software does something specific to your sector.** Dental practice software handles clinical records, the odontogram and insurance billing. Cal.com does appointments, not that. Switching would leave you halfway.
- **If nobody on the team is comfortable with a server.** When it breaks — and it will — you need someone who can read the logs.
- **If your data requires specific certifications.** Self-hosting doesn’t hand you compliance; it hands you control and also the liability.
 

## When yes, clearly
 
- You pay **per user** and the team has grown.
- You handle **sensitive data** you’d rather keep on your own machine.
- You **already have a server** and someone running it: marginal cost is minimal.
- You need to **change how the tool behaves**, which a closed SaaS won’t allow.
 

## FAQ
 

**Are they genuinely free?** The licence is, with no user limit in the community editions. Some projects reserve advanced features for their paid edition, so check that what you need is in the free version before building anything on it. 

**Can I install several on the same server?** Yes, adding up their memory requirements. Cal.com and Documenso (2 GB each) sit comfortably on an 8 GB machine; adding Chatwoot pushes you to 16 GB for headroom. 

**What if the project gets abandoned?** It’s a real risk: one project we track has 55,000 stars and is archived — no more fixes, not even security patches. That’s why we publish an activity indicator for each one and refresh it automatically. 

**Can I migrate my current data?** It depends on whether your provider lets you export. Check **before** deciding what export format they offer: if all you get is a PDF, the migration will be manual. 

**Do I need programming skills?** To install and maintain, no; you do need to be comfortable with a command line and Docker. To customise the code, then yes. 

*🔎 This article contains affiliate links to Hostinger. [Read our affiliate policy](/en/affiliate-disclosure/).*