Open-Source Help Desk Software and Zendesk Alternatives

Choose by how your team works and what you need to bring with you. If you are leaving Zendesk and want to keep your ticket history, start with Zammad: of the projects here, it is the only one with an official Zendesk importer that we could find. If your support runs through email and you want a light PHP app, look at FreeScout, but expect to buy modules for the knowledge base, customer portal, and reports. For an email and web-form ticket desk with SLAs and a customer portal at no cost, use osTicket. Teams moving off OTRS or running IT service processes should look at Znuny (Zammad also imports from OTRS), and teams that work from email queues and want deep workflow control should look at Request Tracker. Chatwoot fits teams whose support happens mostly in live chat and social messaging rather than email tickets.

Facts below were checked on October 27, 2026, against each project's repository, license files, documentation, and pricing page, which are linked where we use them and listed under Sources. About PickOpenSource explains how we write guides.

Ticket desk, conversation inbox, or chat first

This guide covers the projects in our customer support category. They fall into three groups, and for a Zendesk replacement the group matters more than the brand.

• Ticket desks: Zammad, FreeScout, osTicket, Znuny, Request Tracker, UVdesk, and Frappe Helpdesk turn each request into a ticket with a status and an owner. Start here if you are replacing a ticketing help desk such as Zendesk.
• Conversation inboxes: Chatwoot and LibreDesk gather chat, email, and messaging channels into one shared inbox.
• Chat and bot first: Live Helper Chat's README describes live chat and bots with no ticket queue. Tiledesk centers on AI chatbots that hand off to humans. Agent Desk has AI agents answer first and turns the cases they cannot close into tickets.

If you are replacing Intercom's live chat specifically, see the Intercom alternatives page. For every project we list, browse the customer support category.

The open-source help desks compared

What the free self-hosted version includes

Included means the feature appears in the project's own README or documentation for the free self-hosted version. Paid module means you buy it separately. Paid plan only means it exists but not in the free edition. Not found means we did not find it in the project's own sources. The chat-and-bot-first tools are left out because they are built around conversations rather than a ticket queue.

Zammad

Zammad is a ticket-first help desk built with Ruby on Rails, Vue.js, and GraphQL. Its admin documentation lists channels for web, forms, email, chat, Google, Microsoft 365, and SMS. Social channels cover Facebook, Telegram, and WhatsApp, and a separate category handles phone systems. Built-in features include SLAs, calendars, triggers, macros, webhooks, and report profiles, along with time accounting, a knowledge base, and checklists.

According to the software prerequisites, PostgreSQL 15 or later is the only supported database, and Redis 7 or later plus Nginx or Apache are required. Elasticsearch is optional, but the docs call it strongly recommended; Zammad 7.2 needs Elasticsearch 8.15 or later, below version 10. Docker, Kubernetes, and multi-node setups also need Memcached. Zammad ships Docker images, a Helm chart, and DEB and RPM packages. The latest stable tag is 7.2.2, dated October 8, 2026.

Hosted plans are in euros per agent per month, excluding VAT: Starter from €7 (up to 5 agents), Professional from €16 (up to 35 agents; adds chat, Telegram, and SLAs), and Plus from €25 (unlimited agents; adds Facebook, WhatsApp, and a multilingual knowledge base). The page shows two unlabeled prices per plan, so confirm the billing term before you buy.

FreeScout

FreeScout is a PHP and Laravel help desk for PHP 7.4 through 8.x, with MySQL, MariaDB, or PostgreSQL behind Nginx, Apache, or IIS, and a web installer and updater. Its README lists email over IMAP, POP3, and SMTP, with OAuth for Microsoft 365 and Google Workspace. WhatsApp, Telegram, Facebook, Slack, and live chat are also listed, several of them through modules. It sets no limit on agents, tickets, or mailboxes, supports 33 languages, and has a PWA and mobile apps.

The core is free, but many help desk features are paid modules, sold as non-refundable lifetime licenses for a single instance with lifetime updates. Paid modules include Knowledge Base, End-User Portal, Live Chat, Satisfaction Ratings, Reports, and Workflows, along with WhatsApp, Telegram, Teams, and Time Tracking. AI Integration and S3 Storage are free. We could not verify module prices or confirm an SLA module, so price your list on freescout.net and check SLA needs before you commit.

FreeScout has no first-party cloud; its homepage points to third-party hosts such as PikaPods, Cloudron, and Softaculous, or Docker. The latest release is 1.8.248, from October 17, 2026.

osTicket

osTicket needs PHP 8.2 to 8.4 with mysqli, MySQL 5.5 or later, and IIS or Apache. Its README lists web forms, email, and phone as channels, with no social or chat channels.

The features page lists SLA plans with overdue alerts and escalation, and a customer portal with a knowledge base. It also lists ticket filters, help topics, custom fields, and an auto-responder. Ticket locking stops two agents from answering the same ticket, and advanced search exports to CSV. We could not confirm a built-in reporting dashboard. Hosted osTicket starts at $12 per agent per month with a 30-day trial. The latest release is v1.18.4, from June 17, 2026.

osTicket 2.0 is announced at next.osticket.com as rebuilt from the ground up on Laravel. The page gives no release date, status, or license, only a "Get Notified" signup, so plan around the 1.18 line today.

Znuny

Znuny's README calls it "a continuation of the ((OTRS)) Community Edition" version 6.0.30, and its website describes it as the OTRS Community Edition fork with long-term support. Customers open tickets by email or in a web customer interface. Agents get SLAs, Generic Agent automations, process management, and statistics.

IT service management comes as installable packages for the CMDB, incident and problem management, service levels, and change management. A free FAQ package works as the knowledge base. Znuny runs on Linux with Perl, on MySQL, MariaDB, PostgreSQL, or Oracle; the README recommends Apache with mod_perl. The install docs offer a source tarball or an RPM, and we found no official Docker image. Two lines are current on the releases page: 7.3.8 and the LTS 6.5.26, both released October 14, 2026.

Request Tracker

Request Tracker (RT) is a ticket tracker from Best Practical, licensed GPL-2.0. Its README asks for Perl 5.26.3 or later with MySQL, MariaDB, PostgreSQL, or Oracle, behind Apache or nginx. Requests come in by email at queue addresses, through the web UI and a self-service portal, or through a REST 2 API. Scrips run conditions and actions on ticket changes.

The product page and docs list SLAs with business hours, Articles for canned answers, dashboards with scheduled email reports, time tracking, and assets. Installation is a build from source, and the README warns that the built-in server is not for production. Cloud RT starts at $15 per user per month, billed annually, with a 5-user minimum. The latest release is 6.0.3, from May 20, 2026.

UVdesk

UVdesk Community is a ticket desk built on Symfony, licensed OSL-3.0. Its README lists email-to-ticket from unlimited mailboxes, a customer support center, a knowledge base and FAQ, automated workflows, and saved replies, with unlimited agents and tickets. It installs with Composer or a web installer and needs PHP 8.1, MySQL, and the IMAP and Mailparse extensions.

We found no SLA feature in the README, and reporting is a paid app from the Webkul store. A hosted version starts at $11 per agent per month, or $8 billed annually. Check maintenance before you commit: the latest release is v1.1.8, from September 19, 2025, though the repository had a commit on October 7, 2026.

Frappe Helpdesk

Frappe Helpdesk is a ticket desk on the Frappe Framework, using Redis with RediSearch for article search. Its repository covers installing with easy-install.py, bench, or Docker for development, and lists agent and customer portals, SLAs, assignment rules, a knowledge base with article suggestions, and saved replies. Tickets arrive by email, through the portal, or from logged telephony calls, and an Analytics view shows each ticket's timeline and response times. Frappe Cloud hosting starts at $5 a month, priced on hosting rather than per agent, with a 14-day trial. The latest release is v1.31.0, from October 14, 2026.

Chatwoot

Chatwoot is a conversation inbox. Its README lists website live chat, email, and SMS, plus Facebook, Instagram, Twitter, WhatsApp, Telegram, and Line. Agents get reports, CSAT, a Help Center portal, canned responses, auto-assignment, and the Captain AI assistant. The self-hosted requirements are Ruby on Rails and Vue with PostgreSQL (the only supported database), Redis 7 or later, Sidekiq, and at least 4 GB of RAM. Version 4.19.1 shipped on October 24, 2026.

The code is MIT licensed except the enterprise directory, which falls under the Chatwoot Enterprise License and needs payment for production use. Self-hosted plans start with a $0 Community edition, then a $19 per agent per month support tier, then Enterprise at $99 per agent per month, which adds SSO/SAML and SLA policies. So the free Community edition has no SLA policies. Chatwoot Cloud runs from a $0 Hacker plan (2 agents, 500 conversations a month) through $19, $39, and $99 per agent per month.

LibreDesk

LibreDesk is a conversation inbox written in Go and Vue 3 on PostgreSQL. Its README offers a Docker image or a single binary. It handles email, live chat, and WhatsApp through Meta's Cloud API. For support teams it adds SLA management with at-risk alerts, automations, macros, and auto-assignment. It also has CSAT and reporting, a multilingual help center, OIDC single sign-on, and webhooks. Version 2.9.0 came out on October 22, 2026.

Tiledesk, Live Helper Chat, and Agent Desk

Per its repository, Tiledesk builds AI chatbots that hand conversations to humans across web, WhatsApp, Messenger, and Telegram, on Node.js and MongoDB with Docker Compose or Helm. Cloud Pro is €149 a month for 3 users.

Live Helper Chat adds messaging channels to live chat, including Telegram, Viber, Discord, Messenger, Instagram, WhatsApp, and SMS. Bots can run through ChatGPT, Gemini, Ollama, Rasa, or Dialogflow, and agents get voice, video, and screen sharing. Its README describes no ticket queue, so pair it with a ticket desk if you need one.

Agent Desk has AI agents answer from a knowledge base and hand off to humans, and cases become tickets. Its channels are a web chat widget or SDK and an Open API; email is not listed.

Help desk licenses: AGPL, OSL, GPL, Apache, and MIT

Zammad, FreeScout and its modules, Frappe Helpdesk, and LibreDesk use the GNU AGPL-3.0. For a self-hosted help desk, the practical condition is this: if you modify the code and let people use the modified version over a network, including customers on your portal, you must offer those users the source of your changes. Running it unmodified does not trigger that condition. This is a summary, not legal advice, so read the license before you ship changes.

UVdesk uses the Open Software License 3.0, which also treats offering the software over a network as distribution, so the same caution applies. osTicket's and Request Tracker's GPL-2.0 and Znuny's GPL-3.0 have no such network clause. Live Helper Chat and Agent Desk use Apache-2.0, and Tiledesk's umbrella repository is MIT. Chatwoot is MIT except its enterprise directory, which needs a paid license in production.

Moving from Zendesk or OTRS to an open-source help desk

Zammad documents official importers for Zendesk, Freshdesk, Kayako, and OTRS in its migration guides. The Zendesk importer needs a Zendesk plan with API access and an API key from a full admin. It imports groups, organizations, users, and tickets, but not passwords, so users will need new ones. There is no differential migration: each run is a full import, so plan one cutover rather than syncing changes over several days.

Znuny documents an update path from OTRS: from OTRS Community Edition 6.0.x to Znuny 6.1, then one version at a time. Versions before 6.0 are not supported.

We found no official Zendesk importer for FreeScout, osTicket, Znuny, Request Tracker, UVdesk, Chatwoot, or the other projects, and no official Help Scout importer for any of them. With those, start with an empty help desk or write your own import. For more replacements, see the Zendesk alternatives page.

How to choose

1. Decide whether you need tickets, a conversation inbox, or a chat-first tool.
2. If you must keep Zendesk history, run Zammad's importer against a test install before cutover.
3. List what you need on day one, such as SLAs, a knowledge base, a portal, reports, and SSO, then check which are free. FreeScout sells several as modules, and Chatwoot puts SLA policies and SSO in its $99 Enterprise plan.
4. Match the stack to what your team already runs: PHP and MySQL for FreeScout, osTicket, and UVdesk; Perl for Znuny and Request Tracker; PostgreSQL and Redis for Zammad and Chatwoot; a Go binary on PostgreSQL for LibreDesk.
5. Read the license, especially if you plan to modify an AGPL-3.0 project.
6. Pilot with one mailbox or chat widget and a few agents before moving the whole team.