Below is the list of free ftp client tools that I have compiled. These have been mentioned in alphabetical order.

ALFTP -ALFTP is an FTP client and personal FTP server utility from ESTsoft for Microsoft Windows. It is one in the ALTools product family

Amitradecenter-Amitradecenter is a free FTP client with ADT support. It supports several features like parsing of FTP url's, changing directory and file permissions etc..

cURL-cURL is a command line tool for transferring files with URL syntax. The strong point of cURL is the number of data transfer protocols it supports.

CurlFtpFS -CurlFtpFS is a filesystem for accessing FTP hosts based on FUSE and libcurl, which offers the following features amongst others SSLv3 and TLSv1 support;the ability to connect through tunneling HTTP proxies;automatic reconnection upon FTP server time-out.

Cyberduck -Cyberduck is a graphical open source FTP and SFTP client for Mac OS X licensed under the GPL. It supports FTP/TLS (FTP secured over SSL/TLS), using AUTH TLS as well as uploading and downloading by drag and drop and is able to synchronise files and directories. In addition, it is also able to open some files in external text editors.

F->IT-F->IT is an easy to use FTP client that resembles Windows Explorer. It supports drag-drop, editing files and uploading multiple files.

FileZilla Client-FileZilla Client (also referred to as FileZilla) is a free, open source, cross-platform FTP client. It is the most popular free FTP client

Fling-Fling is an FTP Client for Windows and is part of an FTP Client software project by NCH Software. It utilises Windows explorer instead of a typical FTP Client interface with transfers made from the right mouse click menu. It allows you to set a Windows folder as a Fling Folder so that if a file within the folder is changed it will automatically upload the file once it detects a files has been modified and saved.

FtpCube-FtpCube is a multi-platform, graphical (S)FTP client written in Python, using the wxPython graphical tookit. FtpCube's interface is based on LeechFTP which is described below.

Fugu-Fugu is an SFTP client for Mac OS X developed by the University of Michigan's Research Systems Unix Group (RSUG). It is a graphical shell for OpenSSH tools that provides a simple interface to all their features.

gFTP-gFTP is a free/open source multithreaded FTP client. It is most used on Unix-like systems, such as Linux and Mac OS X. It includes both a GUI (which utilizes the GTK+) and a command-line interface.

Kasablanca-Kasablanca is an ftp client, written in c++, using the kde libraries. among its features are currently encryption (auth tls) support, fxp, site bookmarks, and queued transfers.

KFTPgrabber-KFTPgrabber is a graphical FTP client for the K Desktop Environment. It implements many features required for usable FTP interaction. It has amny features like displaying traffic graph and setting upload/download limit. It also supports TSL and SSL.

LeechFTP-LeechFTP was a multi-threaded freeware FTP client with a download failure recovery queue feature. The product was originally written in Delphi 3. The last release, version 1.3 build 207, was made public in April 1999. Afterwards, the project was ended and the author moved on to develop a commercial trialware FTP client called BitBeamer, with more features and browser download integration.

lftp-lftp is a command-line file transfer program (FTP client) for UNIX and Unix-like systems. It was written by Alexander Lukyanov, and is made available under the GNU General Public License.

MacFusion-MacFusion is a file manager for the mac operating system. It also supports secure FTP letting users modify files over FTP as if they were on their own computer.

Mosaic-Mosaic is the browser which popularised the World Wide Web. It also supports FTP operations.

MOVEit Freely-MOVEit Freely is a free command line FTP/secure FTP SSL (FTPS) client for Windows Vista Business Edition, 2003, XP, 2000, ME and NT 4.0 systems.

NcFTP-NcFTP was the first alternative FTP client program, which debuted in 1990. It was created as an alternative to the standard UNIX ftp program, and offers a number of additional features and greater ease of use.
NcFTP is a command-line user interface program, and runs on a large number of platforms.

net2ftp-net2ftp is a web based FTP client, written in PHP.As well as offering standard FTP functions, net2ftp also offers a variety of features including archiving and extracting files and directories, downloading a selected group of files and/or directories as an archive. It can also be set to restrict connections via an access list and can log user actions.

WinSCP-WinSCP (Windows Secure copy) is an open source SFTP and FTP client for Microsoft Windows. Its main function is secure file transfer between a local and a remote computer. Beyond this, WinSCP offers basic file manager functionality. For secure transfers, it uses Secure Shell (SSH) and supports the legacy SCP protocol in addition to SFTP.