Ask for an SFTP client for Windows and someone will recommend WinSCP. That is a good answer, often the right one, but it may not answer the question you meant to ask.
Most people are not especially interested in transferring files. They want to edit a configuration file, open a project, browse a server, or work with remote files as if they were already on their PC.
Those are two different jobs. Transfer clients copy files between your computer and a server. Mounting tools make the server appear as a drive in Windows.
Once you see that distinction, choosing the right tool gets much easier.
Transfer clients: WinSCP, FileZilla, and Cyberduck
Traditional SFTP clients give you a window for moving files back and forth. They are ideal for uploads, downloads, backups, deployments, and any task where the transfer itself is the point.
WinSCP, the Windows default for good reason
WinSCP is free, open source, and built specifically for Windows. It supports SFTP, SCP, FTP, FTPS, WebDAV, and S3.
Its two-pane interface makes it easy to move files between local and remote folders, and an Explorer-style single pane is available for people who prefer it. WinSCP also has transfer queues, folder synchronization, and tight integration with PuTTY and its Pageant authentication agent.
Where WinSCP separates itself is automation. Its scripting interface and .NET assembly make it the natural choice for scheduled transfers, repeatable deployment jobs, and Windows workflows that run without anyone at the keyboard.
If you need to move files, or automate moving them, WinSCP is the place to start.
FileZilla, simple, familiar, and cross-platform
FileZilla is also free and open source, and unlike WinSCP it runs on Windows, macOS, and Linux. It supports FTP, FTPS, and SFTP.
It has fewer Windows-specific features and less emphasis on scripting, and that simplicity is part of its appeal. You connect to a server, see local files on one side and remote files on the other, and drag files between them.
For straightforward manual transfers, that is all you need.
Cyberduck, a bridge between servers and cloud storage
Cyberduck takes a different approach. Instead of the two-pane layout it uses a browser-style interface. It runs on Windows and macOS and supports not only SFTP and FTP but also Amazon S3, Microsoft Azure, Google Drive, OneDrive, Dropbox, and Cryptomator vaults.
Its external-editor feature is useful for quick changes: Cyberduck downloads a remote file, opens it in your chosen editor, and uploads the revised version when you save. That feels close to editing in place, but a transfer is still happening behind the scenes. The ExpanDrive and Cyberduck comparison covers where each fits.
And that is true of all three applications. Before another program can use a remote file, the client copies it to your computer. When you are finished, it copies the file back.
Mounted drives: working with remote files directly
If you spend much of your day inside remote folders, downloading and uploading files over and over gets tedious.
A mounted SFTP connection solves a different problem. Instead of opening a separate transfer client, you assign the server a drive letter. It appears in File Explorer alongside your local disks, and you open remote files directly from editors, office applications, development tools, and every other Windows program. The mounting tool handles network access and caching in the background.
sshfs-win, the open-source route
sshfs-win combines two open-source components: the WinFsp file-system driver and a Windows port of SSHFS.
Once installed, it maps an SFTP server from the command line or the Map Network Drive dialog using a special network path. The result is a remote server that appears as a normal Windows drive.
It works, and it costs nothing, but it asks a little more of the user. You are installing a file-system driver, working with a connection syntax, and handling credentials by hand. There is no connection manager for a large collection of servers. For technical users who prefer open-source components and do not mind the setup, it is a capable option, and the sshfs guide walks the Windows setup step by step.
ExpanDrive, SFTP as a managed Windows drive
ExpanDrive reaches the same outcome as an application. You create an SFTP connection, assign it a drive letter, and the remote server appears in Explorer.
Authentication uses a password, an OpenSSH key, or Pageant, so existing PuTTY-based keys keep working. Custom ports and remote root folders are settings rather than command-line flags. Files stream on demand, with a local cache for performance.
ExpanDrive also mounts FTP, WebDAV, S3, and the consumer cloud services, so different kinds of remote storage appear in Windows through the same application.
For business environments it installs from a signed MSI with silent-install options, which matters when it has to land on many PCs. It is free for personal use. The Windows specifics are on the SFTP client for Windows page, and the cloud drive for Windows page covers everything else it mounts.
Which SFTP client to choose
Start by asking what you actually do with the server.
WinSCP fits if you regularly upload and download files, need synchronization or transfer queues, want to automate transfers with scripts or .NET, and prefer a free, Windows-native tool.
FileZilla fits if you want a simple drag-and-drop transfer client, work across several operating systems, and do not need Windows-specific integration or automation.
Cyberduck fits if you use SFTP servers and cloud storage side by side, prefer a browser-style interface, and occasionally edit remote files through an external editor.
sshfs-win fits if you want the server mounted as a Windows drive, prefer an open-source solution, and do not mind command-line configuration and manual setup.
ExpanDrive fits if you want a drive letter with minimal setup, need OpenSSH or Pageant authentication, manage several remote connections, and have to deploy the same configuration across many Windows PCs.
You may want both
There is no rule that says you must pick one approach.
A transfer client is excellent for one-off uploads, bulk downloads, scripted jobs, and deployments. A mounted drive is better for the server you work in every day, the one whose files you want to open from your editor without thinking about transfers.
Use WinSCP for moving files. Mount the servers you live in. The best Windows SFTP setup is often a combination of both.