HIPAA Transmission Security Standard (45 CFR 164.312(e))
Required standard to guard against unauthorized access to ePHI transmitted over an electronic communications network, with addressable specs for integrity controls and encryption.
Primary source
45 CFR 164.312(e) — eCFR →https://www.ecfr.gov/current/title-45/subtitle-A/subchapter-C/part-164/subpart-C/section-164.312#p-164.312(e)
Verified May 23, 2026 · This is the authoritative regulator URL. The summary below is a research aid; the linked source controls.
45 CFR 164.312(e)) requires technical security measures to guard against unauthorized access to ePHI being transmitted over an electronic communications network.
Two addressable specifications: integrity controls (security measures to ensure that ePHI is not improperly modified without detection until disposed of); and encryption (a mechanism to encrypt ePHI whenever deemed appropriate).
Addressable does not mean optional. The risk analysis must justify whether each spec is reasonable. For ePHI traversing the public internet, the defensible answer to encryption is yes — TLS 1.2 or higher with current cipher suites, evolving as protocols deprecate (TLS 1.0/1.1 are no longer acceptable). End-to-end encryption (S/MIME or similar) for email containing PHI is the cleaner posture; opportunistic TLS at the SMTP gateway is the practical minimum.
OCR's encryption Safe Harbor in the Breach Notification Rule at 164.402 means properly encrypted ePHI lost in transit is not subject to breach notification — an outsized business and operational benefit that pulls many practices to encrypt by default.
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Related across the archive
- RegulationHIPAA Security Access Control (45 CFR 164.312(a))Technical policies and procedures for systems containing ePHI to allow access only to those granted access rights, with required specifications for unique user identification and emergency access.
- RegulationHIPAA Technical Safeguards (45 CFR 164.312)Five standards covering access control, audit controls, integrity, person or entity authentication, and transmission security for ePHI.
- RegulationHIPAA Security Rule: General Rules (45 CFR 164.306)Required objectives — confidentiality, integrity, and availability of ePHI — plus the flexibility provisions that govern how covered entities select and implement specific safeguards.
- RegulationHIPAA Audit Controls Standard (45 CFR 164.312(b))Required technical safeguard: implement hardware, software, and procedural mechanisms that record and examine activity in information systems containing ePHI.
- ComplianceHIPAA Encryption Policy Template (45 CFR § 164.312(a)(2)(iv) + (e)(2)(ii))2026 HIPAA encryption policy template — 45 CFR § 164.312(a)(2)(iv) at-rest, § 164.312(e)(2)(ii) in-transit, NIST SP 800-111 algorithms, key management.
- SRAChange Healthcare Ransomware: What Small Practices Took AwayThe February 2024 Change Healthcare cyberattack, what HHS and UnitedHealth Group disclosed, and the small-practice lessons about clearinghouse concentration risk, contingency planning, and the Security Rule's information system activity review.
- GlossaryAccess ControlsTechnical policies and procedures that allow only authorized persons or software programs to access ePHI.
- BillingBusiness Associate Agreement Checklist for Small PracticesA working checklist for small practices to identify which vendors need a Business Associate Agreement, what clauses the BAA must contain, and how to track them.
Last reviewed May 23, 2026 · Citation verified May 23, 2026
Research aid, not legal advice. This summary is an administrative research aid prepared by D3rx. It does not certify compliance, provide legal advice, replace counsel, or guarantee an audit outcome. For authoritative regulatory text follow the primary source link at the top of this page. The practice remains responsible for reviewing, adopting, and maintaining its compliance program.