SFTP vs. FTPS: Key Differences Explained

Data security is crucial, businesses can’t afford to take risks with file transfers. From financial records to customer information and confidential business documents, sensitive data is constantly moving between systems, partners, and cloud environments. Without the right security measures, these transfers become vulnerable to cyber threats, data breaches, and compliance violations.

To protect critical information, businesses rely on secure file transfer protocols like Secure Transfer’s SFTP and FTPS (FTP Secure). While both provide encrypted alternatives to traditional FTP, they differ in architecture, security mechanisms, and configuration requirements. Choosing the right protocol is more than just a technical decision—it can impact network performance, regulatory compliance, and overall data security.

We break down the key differences between SFTP and FTPS, exploring their advantages, disadvantages, and ideal use cases to help businesses make an informed choice for secure file transfers.

Key Insights: SFTP vs. FTPS – Key Differences Explained

Security architecture: SFTP operates over SSH (Secure Shell), encrypting the entire session, while FTPS enhances traditional FTP with TLS/SSL encryption for data protection.

Firewall configuration: SFTP uses a single port (typically port 22), making it easier to configure and secure, whereas FTPS requires multiple ports, complicating firewall management.

Authentication methods: SFTP supports password-based authentication and SSH keys, offering stronger security for automated file transfers, while FTPS relies on username-password authentication and optional SSL certificates.

Data transfer efficiency: FTPS may be slightly faster in some scenarios since SFTP encrypts all commands and data, which can introduce processing overhead. However, modern systems handle encryption efficiently, making the speed difference negligible for most users.

Compliance and industry standards

Both SFTP and FTPS can meet security regulations such as HIPAA, GDPR, and PCI-DSS, but SFTP is often preferred due to its stronger encryption and simplified security controls.

Compatibility and integration

FTPS is a natural choice for organizations that already use FTP infrastructure and need to add encryption, while SFTP is ideal for businesses adopting modern, automated, and script-based file transfers.

Use case considerations

SFTP is better suited for secure enterprise environments, automated workflows, and cloud integrations, while FTPS may be preferable for organizations with legacy FTP systems that require encryption without a complete protocol switch.

Risk and vulnerability management

SFTP’s single-connection architecture and SSH-based encryption make it inherently more secure, while FTPS requires careful configuration to prevent vulnerabilities associated with passive mode connections.

Understanding Secure File Transfer Protocols

Transferring files across networks has been a fundamental need since the early days of computing, but as technology evolved, so did the risks. File Transfer Protocol (FTP) was originally designed as a simple method for moving files between systems, but it came with a critical flaw—a complete lack of security. Traditional FTP sends usernames, passwords, and data in plaintext, making it an easy target for cybercriminals who can intercept and manipulate sensitive information.

To address these vulnerabilities, secure file transfer protocols were developed, providing encryption and authentication to protect data during transit. The two most widely adopted secure alternatives are:

• SFTP (Secure File Transfer Protocol): A modern, security-first protocol built on SSH (Secure Shell). It encrypts both authentication credentials and file transfers, ensuring that data remains protected from unauthorized access and interception.

• FTPS (FTP Secure): A more traditional extension of FTP that incorporates TLS/SSL encryption. It enhances security by encrypting data in transit but retains much of the original FTP structure, making it a familiar option for organizations already using FTP.

While both SFTP and FTPS offer encryption, their underlying technologies, authentication methods, and security implementations differ significantly. Choosing between them depends on factors such as network configuration, compliance requirements, automation needs, and overall security priorities. Understanding these differences is key to selecting the most effective and secure file transfer solution for your business.

What is SFTP?

SFTP (Secure File Transfer Protocol) is a secure alternative to traditional FTP, designed to encrypt file transfers and protect sensitive data. Unlike standard FTP, which transmits data in plaintext and exposes credentials to potential interception, SFTP operates over SSH (Secure Shell), ensuring that both authentication and file transfers are fully encrypted. This makes SFTP one of the most widely used and trusted protocols for secure file exchanges across industries such as finance, healthcare, and enterprise IT.

How SFTP Works

SFTP simplifies secure file transfers by using a single, encrypted connection, reducing security risks and making network configuration easier. Here’s how it functions:

• Runs on a single port (default: port 22) – Unlike FTPS, which requires multiple ports, SFTP’s single-connection approach makes it firewall-friendly and easier to manage.

• Supports SSH key or password authentication – Businesses can enhance security by eliminating passwords and requiring public-key authentication.

• Encrypts all data, commands, and credentials – Everything sent over SFTP is fully protected, preventing unauthorized access and tampering.

Security Features of SFTP

SFTP is one of the most secure file transfer methods available, thanks to its strong encryption and authentication mechanisms. Key security features include:

• End-to-end encryption – Uses AES, RSA, or ECC cryptographic algorithms to ensure that files are unreadable during transit.

• Key-based authentication – Reduces reliance on passwords by allowing authentication through SSH key pairs, significantly strengthening security.

• Data integrity checks – Ensures that files are not altered, corrupted, or compromised during transfer.

Advantages of SFTP

• Stronger security – Unlike FTPS, SFTP encrypts the entire session, including authentication, data transfer, and commands.

• Simplified firewall configuration – Operates on a single port (22), making it easier to manage security policies and firewall rules.

• Better authentication options – Supports SSH key authentication, eliminating the risks associated with weak passwords.

• Broad compatibility – Natively supported in Unix/Linux environments, making it a preferred choice for enterprise IT infrastructure.

Disadvantages of SFTP

• Slightly slower than FTPS – The encryption process introduces minimal overhead, which may slightly impact transfer speeds.

• Limited support in older Windows environments – Some legacy systems may require additional configuration to support SFTP.

• Requires SSH key setup for optimal security – While SSH keys improve security, their setup and management can be complex for non-technical users.

SFTP is the go-to choice for organizations prioritizing security, compliance, and automation, making it an ideal solution for sensitive data transfers and enterprise-level file exchanges.

What is FTPS?

FTPS (FTP Secure) is a modernized version of FTP, designed to protect file transfers with encryption and authentication. Unlike traditional FTP, which transmits credentials and data in plaintext, FTPS secures communication by leveraging TLS (Transport Layer Security) or SSL (Secure Sockets Layer) to encrypt data, preventing unauthorized access and interception.

FTPS is widely used in corporate and legacy environments where organizations need to add security to existing FTP infrastructure without switching to a completely new protocol like SFTP.

How FTPS Works

FTPS operates by securing file transfers with TLS/SSL encryption, ensuring that data, authentication credentials, and commands remain protected throughout the session. However, FTPS differs from SFTP in that it requires multiple ports to function, which can make network configuration more complex.

FTPS can be implemented in two distinct modes:

• Explicit FTPS (Port 21): Encryption is negotiated after connection using TLS commands. This allows backward compatibility with legacy FTP systems that may not require encryption.

• Implicit FTPS (Port 990): Encryption is mandatory before the connection is established, ensuring that all transmissions are secure from the start.

Because FTPS uses one port for commands and separate dynamic ports for data transfer, firewall configuration must be carefully managed to avoid connectivity issues.

Security Features of FTPS

FTPS enhances the traditional FTP protocol with robust security mechanisms, including:

• TLS 1.2/1.3 or SSL encryption – Protects data from interception and tampering.

• Username/password authentication and SSL certificates – Supports secure login methods, with the option for client-side certificates for additional verification.

• X.509 certificate authentication – Allows businesses to use digital certificates for client-server authentication, ensuring secure connections.

Advantages of FTPS

• Industry-wide compatibility – Works with legacy enterprise systems that were originally built around FTP, making it a suitable option for organizations with existing FTP infrastructure.

• Strong encryption standards – Uses TLS/SSL to protect file transfers, ensuring confidentiality and integrity.

• Familiar workflow – Retains the command structure and user experience of traditional FTP, making adoption easier for teams already familiar with FTP-based workflows.

Disadvantages of FTPS

• Complex firewall configuration – Requires multiple ports for control and data transfer, which can be challenging to configure and secure, especially in strict network environments.

• Security vulnerabilities if misconfigured – Some implementations allow unencrypted FTP commands, which can expose credentials and data to potential attacks if not properly set up.

• Limited support in Unix/Linux environments – While FTPS is common in Windows-based enterprise systems, SFTP is more widely used in Linux/Unix environments due to its SSH-based architecture.

FTPS is an ideal solution for businesses looking to enhance security while maintaining compatibility with legacy FTP systems. However, organizations prioritizing firewall simplicity, stronger encryption, and automation may find SFTP a better alternative for secure file transfers.

Key Differences Between SFTP and FTPS

While both SFTP and FTPS provide secure alternatives to traditional FTP, their underlying technologies, security implementations, and network configurations differ significantly. Choosing the right protocol depends on security needs, infrastructure compatibility, and performance considerations. Here’s how they compare:

1. Encryption and Security

• SFTP: Uses SSH-based encryption, ensuring that all data, commands, and authentication credentials are encrypted end-to-end. This makes SFTP highly secure and resistant to interception or tampering.

• FTPS: Relies on TLS/SSL encryption, which protects data but may still allow unencrypted FTP commands in certain configurations. This creates potential vulnerabilities if not set up correctly.

2. Authentication Methods

• SFTP: Supports password authentication but is best known for SSH key-based authentication, which is considered more secure and ideal for automation.

• FTPS: Uses username/password authentication and also supports X.509 certificates, allowing businesses to use TLS-based client authentication for added security.

3. Firewall and Network Configuration

• SFTP: Operates on a single port (port 22), making it easier to configure firewalls and reduce security risks.

• FTPS: Requires multiple ports—one for commands and additional ports for data transfer—complicating firewall setups and increasing potential security gaps.

4. Performance and Speed

• SFTP: Encrypts the entire session, including commands and file transfers, which adds processing overhead and can make it slightly slower. However, the difference is negligible on modern systems.

• FTPS: Can be faster in some scenarios, but its multi-port architecture can slow performance in restricted network environments where firewall rules impact data flow.

5. Compatibility and Support

• SFTP: Natively supported on Linux and Unix servers, making it the go-to choice for enterprises using open-source or cloud-based infrastructure.

• FTPS: More commonly found in Windows-based enterprise environments where organizations want to add security to existing FTP workflows without switching to a completely new protocol.

When to Choose SFTP vs. FTPS

Best Use Cases for SFTP:

✔ High-security industries such as finance, healthcare, and government that require strong encryption and secure authentication.
✔ Organizations that prioritize security and encryption over raw speed.
✔ Businesses running on Linux/Unix-based servers, where SFTP is natively supported.
✔ Situations where firewall simplicity is important, since SFTP requires only one port (22).
✔ Environments requiring automated, script-based file transfers that benefit from SSH key authentication.

Best Use Cases for FTPS:

✔ Enterprises with legacy FTP infrastructure that need to add security without a complete protocol switch.
✔ Businesses that require TLS/SSL certificate-based authentication for regulatory compliance.
✔ Organizations needing compatibility with Windows-based systems where FTPS is more commonly integrated.
✔ Workflows that involve third-party vendors or partners who already use FTP and require an encrypted extension of the existing protocol.

By understanding the key differences and use cases, businesses can select the right protocol to balance security, performance, and compatibility, ensuring safe and efficient file transfers that align with their operational needs.

Compliance and Industry Standards

Both SFTP and FTPS comply with security regulations, including:

• HIPAA (Health Insurance Portability and Accountability Act) – Required for healthcare file transfers.
• PCI-DSS (Payment Card Industry Data Security Standard) – Ensures encrypted credit card transaction data transfers.
• GDPR (General Data Protection Regulation) – Requires encrypted data transfers for compliance in the EU.

However, SFTP is generally preferred for compliance-heavy industries due to its end-to-end encryption and secure key-based authentication.

SFTP vs FTPS: Which One Should You Use?

When deciding between SFTP and FTPS, consider security, compatibility, and network configuration:

• If security is the top priority, SFTP is the better choice due to SSH-based encryption and a simpler firewall setup.
• If you need to maintain compatibility with existing FTP infrastructure, FTPS provides a natural upgrade path.
• For automated workflows and cloud integrations, SFTP offers better support and stronger authentication options.
• In regulated industries, both protocols meet compliance requirements, but SFTP’s end-to-end encryption provides additional security benefits.

The choice between SFTP and FTPS ultimately depends on your specific requirements, existing infrastructure, and security priorities. Both protocols provide significant security improvements over traditional FTP, ensuring that your file transfers remain protected in today’s increasingly complex threat landscape.