There is no shortage of Confluence competitors on the market but if I had to pick a single best free Confluence alternative, that would be Bitrix24 for sure. If you are not familiar, Bitrix24 is Confluence (team collaboration) plus Jira (Helpdesk and tickets) plus HipChat (enterprise mobile) plus Basecamp (project management) plus Dropbox (file sharing and doc management) plus Salesforce (CRM) plus Skype (web phone calls and videoconferencing) plus GoogleCalendars (shared calendars) and 35+ other odd tools (like human resources information system) – and all of that free for teams of up to 12 users. Pretty cool, ain’t it?

Atlassian is a great company and its products - be that Altassian Confluence or Jira or BitBucket - are rightfully praised. But these are products made by programmers for programmers and when it comes to ‘normal’ business (if there’s such a thing), Confluence frequently falls short.

So why do I  believe that Bitrix24 is best Confluence alternative other than the fact that it’s free and comes with so many tool?

First, it’s the fact that you have an option to use cloud service or the self-hosted version (that comes with the source code and API, by the way, so you can modify it as you see fit, if you have PHP programming skills). I hate when you are given cloud only option and are forced to pay every month. With Bitrix24 you can move from cloud to your own server any time you want.

Second is the fact that all the tools work out of the box. If you are familiar with Microsoft product line, try to imagine if you had to integrate SharePoint with Yammer for enterprise social with MS Project for PM with Lync for communications with Dynamics for CRM – that would take you at least a couple of days. With Bitrix24 everything works right away.

Finally – CRM. For some reason, there is not a single decent enterprise social network that comes with a CRM. Salesforce Chatter is as close as it gets. And while Salesforce is a great product, paying $60-$220 per single user is very, very expensive for an average small business. (The CRM in Bitrix24 is fully featured and comes with Invoicing, Mobile CRM, CRM activity stream, email marketing and other goodies – no limits on a number of contacts or any of that nonsense).

As far as disadvantages go, these rise from the fact that Bitrix24 in not IT centric – don’t expect integrations with BitBucket or GitHub. Bitrix24 can be used for bug tracking, but it probably shouldn’t be. Documentation is not as complete either. That said, you absolutely should try Bitrix24, because it will blow your mind (it did mine).

And if you think that there’s a better free Confluence alternative than Bitrix24, do let me know.

Source - Best Free Confluence Alternative