If you are managing a website, you have likely moved past the old, insecure FTP. In today's time, transferring files without encryption is a massive security risk.
But this leaves you with two alphabet-soup options that look nearly identical: SFTP and FTPS.
While they share similar letters, they are completely different technologies under the hood. For most of our clients—from developers to business owners—choosing the right one affects your security, your firewall configuration, and even your transfer speed.
Here is the definitive guide on the differences and which one we recommend for your workflow.
The Short Answer
- Use SFTP (Secure File Transfer Protocol) if you want the modern standard. It is easier to set up, works better through firewalls, and is the choice for developers and automation.2
- Use FTPS (File Transfer Protocol over SSL) if you have a legacy application that specifically requires it, or if you need to support older system architectures that don't understand SSH.
The "Engine" Difference: SSH vs. SSL
To understand the difference, you have to look at how they build the secure tunnel.
1. SFTP (SSH File Transfer Protocol)
SFTP was built from the ground up as a secure protocol. It runs over SSH (Secure Shell).
- How it works: It uses a single secure channel to send both commands ("upload this file") and data (the actual file).
- The Benefit: Because it lives on the SSH protocol, it is incredibly robust.7 If you can SSH into a server, you can usually SFTP into it without extra configuration.
2. FTPS (FTP over SSL/TLS)
FTPS is essentially the old FTP protocol wrapped in a layer of encryption (SSL/TLS), similar to how HTTPS wraps HTTP.
- How it works: It uses two separate channels: one for commands and one for data.
- The Benefit: It is backward compatible with older FTP systems, making it familiar for users who have been using FTP since the 90s.
The Big Battle: Firewalls & Ports
This is where SFTP usually wins the debate for IT administrators and hosting providers.
The FTPS Headache
FTPS is notoriously difficult to configure with firewalls. Because it uses two separate channels, it requires multiple ports:
- Port 21 (or 990): For the command channel.
- Passive Port Range: A random range of ports (e.g., 30000–50000) for the actual data transfer.
If your firewall blocks that random port range, your client will connect successfully but hang endlessly when trying to list a directory or upload a file. This is the #1 support ticket we see regarding FTP.
The SFTP Simplicity
SFTP is beautiful in its simplicity. It uses one single port (usually Port 22) for everything.
- commands? Port 22.
- Data? Port 22.
- Authentication? Port 22.
If Port 22 is open, SFTP works. Period.
A Note on Speed
You might read old articles claiming "FTPS is faster." Technically, FTPS has less packet overhead than SFTP. However, in today's time, with modern CPU power and optimized clients (like FileZilla or WinSCP), the difference is negligible for 99% of users.
Unless you are transferring terabytes of data daily within a private internal network, you will not notice a speed difference.
Which One Should You Choose?
Choose SFTP if:
- You are a developer or working on a Linux server.
- You value security and want to use SSH Keys (passwordless login) for automation.16
- You are working behind a strict firewall or NAT.
- You want to avoid "Directory Listing Failed" errors.
Choose FTPS if:
- You are on a shared hosting plan that only provides FTP accounts (and no SSH access).
- You are using legacy software that strictly requires an FTP connection type.
- You need central SSL certificate management for compliance reasons in a Windows environment.
The Verdict
For modern web hosting, SFTP is the clear winner. It is more secure by design, easier to troubleshoot, and integrates perfectly with modern development workflows.