SFTP vs FTPS: why SFTP is usually the simpler default

People often treat “SFTP” and “FTPS” as interchangeable because the names look alike. They aren’t the same protocol, and the difference that matters in practice isn’t security (both are secure when configured correctly), it’s how much operational complexity each one brings to a modern cloud setup.

Here’s the honest comparison, and when each is the right call.

They are different protocols, not spellings

• SFTP is the SSH File Transfer Protocol. It runs inside an SSH session, over a single connection on a single port (usually 22). Authentication and encryption are SSH’s.
• FTPS is the original FTP (RFC 959) wrapped in TLS (RFC 4217). It keeps FTP’s design: a control connection plus separate data connections, secured with TLS certificates.

Both encrypt credentials and data in transit. Neither is “more secure” than the other in the abstract. The divergence is everything around the encryption.

Where the complexity lives

FTPS inherits FTP’s two-channel architecture, and that’s the operational catch:

	SFTP	FTPS
Transport	SSH, single connection	FTP control + separate data connections
Ports	One (typically 22)	Control port plus a range of passive data ports
Encryption setup	SSH keys / known-hosts	TLS certificates to issue, install, and renew
Firewall / NAT	Simple, one port	Must open and track a passive-port range
Through a load balancer / proxy	Straightforward	Awkward, TLS + dynamic data ports fight proxies

In a modern cloud environment those FTPS frictions add up: you manage TLS certificates and their renewal, you open and maintain a passive-port range through firewalls and NAT, and the dynamic data connections make FTPS harder to put cleanly behind a load balancer or a hostname that isn’t the literal certificate subject. SFTP’s single SSH connection sidesteps all of it, which is why it’s the default choice for many cloud storage gateways and managed file-transfer services.

FTPS is a secure protocol when configured correctly. However, its reliance on TLS certificates and multiple data ports makes it more complex to deploy and operate in modern cloud environments. SFTP, running over SSH on a single connection, is simpler to manage, and is the preferred choice for many cloud storage gateways and managed file-transfer services.

When FTPS is still the right pick

SFTP being the simpler default doesn’t make FTPS wrong. Choose FTPS when:

• A partner or legacy system only speaks FTPS. Plenty of established B2B integrations and older appliances were built around FTP/FTPS and can’t switch. Meeting them where they are beats forcing a migration.
• You already operate FTPS infrastructure (certificates, port ranges, monitoring) and the team knows it well.
• A specific tool or compliance process mandates it. Some procurement and audit checklists still name FTPS explicitly.

This is exactly why Firepipe is SFTP-only. Rather than carry FTPS’s certificate and passive-port-range complexity, the gateway commits to the protocol that’s simplest and most robust to operate in front of cloud storage. The honest trade-off: if a partner or system can only speak FTPS, Firepipe isn’t your fit, and we’d rather tell you that up front than pretend otherwise.

What about plain FTP?

Neither of the above is plain, unencrypted FTP, which sends passwords and file contents in cleartext and has no place on the public internet. If “FTP” is on the table at all, it should mean FTPS (FTP-over-TLS), never bare FTP. See why plain FTP is insecure for the detail.

Bottom line

• Both SFTP and FTPS are secure when configured correctly.
• SFTP is simpler to operate in the cloud: one connection, one port, SSH keys, no certificate or passive-port-range management.
• FTPS earns its place when a partner, a legacy system, or a process specifically requires it, in which case you’ll want a gateway that speaks it.
• Firepipe focuses on SFTP for the simplicity and operational robustness above. If SFTP is what you need, see SFTP to S3 or the full guides.