Is faxing more secure than email?

Modern online fax is generally more secure than standard email. Online fax services use TLS encryption in transit and AES-256 at rest, while standard email travels unencrypted by default. Traditional fax machines are also less secure than email because they send analog signals over unencrypted phone lines with no audit trail.

Can a fax be intercepted?

Traditional fax transmissions can be intercepted by tapping phone lines, since the signal is unencrypted analog data. Online fax services protect against this with TLS 1.3 encryption during transit, making interception extremely difficult. Physical documents left in output trays remain a risk for traditional machines. See our guide to [can faxes be intercepted](/blog/can-fax-be-intercepted/) for a full breakdown.

Is online fax HIPAA compliant?

Online fax can be HIPAA compliant when the provider signs a Business Associate Agreement (BAA) and implements required safeguards — including encryption, access controls, and audit logs. Not all online fax services are HIPAA compliant by default; you must verify BAA availability before sending PHI. Learn more in our [HIPAA fax requirements guide](/blog/hipaa-fax-requirements/).

What encryption do fax services use?

Reputable online fax services use TLS 1.2 or 1.3 for encryption during transmission (data in transit) and AES-256 for documents stored on their servers (data at rest). Traditional fax machines use no encryption at all. See our [fax encryption explainer](/blog/fax-encryption/) for technical details.

What is the most secure way to send a fax?

The most secure way to send a fax is through a reputable online fax service that provides TLS encryption in transit, AES-256 at rest, a BAA for HIPAA compliance, two-factor authentication, and full audit trails. Services like mFax Business meet all of these requirements.

Is Fax Secure? Tips & Best Practices Compared (2026)

Is fax secure? The answer depends on how you fax. Traditional machines send unencrypted data over phone lines — but modern online fax services use AES-256 encryption, TLS 1.3, and full audit trails to keep your documents safe.

Frequently Asked Questions

Is faxing more secure than email?: Modern online fax is generally more secure than standard email. Online fax services use TLS encryption in transit and AES-256 at rest, while standard email travels unencrypted by default. Traditional fax machines are also less secure than email because they send analog signals over unencrypted phone lines with no audit trail.
Can a fax be intercepted?: Traditional fax transmissions can be intercepted by tapping phone lines, since the signal is unencrypted analog data. Online fax services protect against this with TLS 1.3 encryption during transit, making interception extremely difficult. Physical documents left in output trays remain a risk for traditional machines. See our guide to [can faxes be intercepted](/blog/can-fax-be-intercepted/) for a full breakdown.
Is online fax HIPAA compliant?: Online fax can be HIPAA compliant when the provider signs a Business Associate Agreement (BAA) and implements required safeguards — including encryption, access controls, and audit logs. Not all online fax services are HIPAA compliant by default; you must verify BAA availability before sending PHI. Learn more in our [HIPAA fax requirements guide](/blog/hipaa-fax-requirements/).
What encryption do fax services use?: Reputable online fax services use TLS 1.2 or 1.3 for encryption during transmission (data in transit) and AES-256 for documents stored on their servers (data at rest). Traditional fax machines use no encryption at all. See our [fax encryption explainer](/blog/fax-encryption/) for technical details.
What is the most secure way to send a fax?: The most secure way to send a fax is through a reputable online fax service that provides TLS encryption in transit, AES-256 at rest, a BAA for HIPAA compliance, two-factor authentication, and full audit trails. Services like mFax Business meet all of these requirements.