Alternatives to PChat-IRC for all platforms with any license

Thunderbird

Thunderbird is a free, open source, cross-platform e-mail, news and instant messaging client. The project strategy is modeled after Mozilla Firefox.

Free Open Source Mac Windows Linux BSD PortableApps.com ... Haiku
Extensible by Plugins/Extensions Built-in RSS reader Built-in Calendar Calendar integration ... Categories Customizable Extensible by Plugins/Extensions Free API Gmail integration Google Calendar integration Import from Google Reader Support for IMAP Integrated Chat Integrated Password Manager Integrated Web Browser IOS support Legacy addons support Multiple Account support Export to OPML Import feeds from OPML POP3 Support Portable Secure File Sharing SMTP integration Tabbed interface Support for Themes Add a feature

1780 Like
HexChat

HexChat is an IRC client based on XChat for Linux , but unlike XChat it’s completely free for both Windows and Unix-like systems. HexChat was...

Free Open Source Windows Linux BSD PortableApps.com Xfce ... MacPorts XQuartz
Portable Add a feature

175 Like
mIRC

mIRC is a popular Internet Relay Chat client used by millions of people, and thousands of organizations, to communicate, share, play and work with each other on IRC...

Commercial Windows
Colored Text Add a feature

84 Like
XChat for Linux

XChat is an IRC chat program for both Linux and Windows. It allows you to join multiple IRC channels (chat rooms) at the same time, talk publicly, private one-on-one...

Free Open Source Windows Linux
No features added Add a feature

103 Like
- Discontinued The program is no longer updated. Last version, 2.8.8, released in May 2010, can be still downloaded from the official website.
irssi

Irssi is a terminal based IRC client for UNIX systems. It also supports SILC and ICB protocols via plugins.

Free Open Source Mac Windows Linux BSD Cygwin
No features added Add a feature

73 Like
KVIrc

KVIrc is a free portable IRC client based on the excellent Qt GUI toolkit. KVirc is being written by Szymon Stefanek and the KVIrc Development Team with the contribution...

Free Open Source Mac Windows Linux BSD PortableApps.com
Portable Add a feature

37 Like
Kiwi IRC

A hand-crafted IRC client that you can enjoy. Designed to be used easily and freely. More friendly than other webirc clients giving the general public an easy option to...

Free Open Source Web Self-Hosted Chrome
Preconfigurable auto-connect Add a feature

20 Like
AdiIRC

c#/csharp IRC CLient. AdiIRC stores all its settings in text files, this way you can grab the adiirc folder and put in on a usb device or external harddrive. Take all...

Free Windows Wine
Portable Add a feature

25 Like
Shout

What is it? Shout is a web IRC client that you host on your own server. What features does it have? * Multiple user support * Stays connected even when you close...

Free Open Source Web Self-Hosted
No features added Add a feature

13 Like
- Discontinued Shout's development has stopped early 2016 and replaced by its official community fork: http://alternativeto.net/software/the-lounge/ . See https://github.com/erming/shout
Chatzilla

ChatZilla is a clean, easy to use and highly extensible Internet Relay Chat (IRC) client, built on the Mozilla platform, which provides all the usual features: multiple...

Free Open Source Mac Windows Linux SeaMonkey Firefox
No features added Add a feature

19 Like
Konversation

Konversation is an easy-to-use IRC client for novices, nut novices and experts can take advantage of its rich featureset.

Free Open Source Linux
No features added Add a feature

21 Like
Qwebirc

qwebirc is a web based AJAX IRC client.

Free Open Source Windows Linux BSD Self-Hosted
No features added Add a feature

7 Like
Convos

Convos is the simplest way to use IRC. It is always online, and accessible to your web browser, both on desktop and mobile.

Free Open Source Web Self-Hosted
No features added Add a feature

5 Like
Maid-IRC

A modern web IRC client. Built on Node.js.

Free Open Source Web Self-Hosted Node.JS
No features added Add a feature

6 Like
X-Chat 2 for Windows

A freeware build of X-Chat for windows, as opposed to the official 30-day-trial shareware Windows build.

Free Windows
No features added Add a feature

22 Like
- Discontinued Author announed EOL on homepage.