IACS UR E26/E27

1. 2026-09-04 Medium
   IACS publishes Unified Requirement E5 revision 1

   IACS has published Unified Requirement E5 revision 1, updating maritime technical standards for classification societies and the shipping industry. This revision introduces changes to previously established …

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1. 2024-07-01 UR E26 Rev.1 and UR E27 Rev.1 apply to ships contracted for construction on or after this date
2. 2024-01-01 Planned application date of the original April 2022 E26 and E27; they were withdrawn before coming into force

1. —
   UR E26 Rev.1 and UR E27 Rev.1 Major versionCurrent

   Complete revisions that superseded the April 2022 originals, standardized survey requirements and split applicability into mandatory and non-mandatory by vessel type and size. source

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   • Both apply to ships contracted for construction on or after 1 July 2024.
   • E27 Rev.1 was published first; IACS said the revised E26 would follow before the end of the year, and the published E26 Rev.1 is dated Nov 2023.
2. —
   UR E26 and UR E27 (original, withdrawn) Major version

   First versions, published in April 2022 for new ships from 1 January 2024; withdrawn before coming into force. source

Mandatory for new ships of the listed types contracted from 1 July 2024; E26 covers the ship as a whole, E27 the on-board systems and equipment.

Vessels in scope

Passenger ships (including high-speed passenger craft) on international voyages; cargo ships and high-speed craft of 500 GT and upwards on international voyages; mobile offshore drilling units of 500 GT and upwards; self-propelled mobile offshore units engaged in construction. source

Non-mandatory guidance

For other ships, such as warships, cargo ships under 500 GT, fishing vessels and yachts, the URs may be used as non-mandatory guidance. source source

Contract date

"Contracted for construction" means the date the contract to build the vessel is signed between the prospective owner and the shipbuilder (see IACS PR No. 29). source

E26, the ship

Minimum requirements for cyber resilience of the ship as a collective entity, organized as Identify, Protect, Detect, Respond and Recover. source

E27, systems and equipment

Requirements for cyber resilience of on-board systems and equipment, applied to the computer-based systems specified in UR E26. source

Navigation and radio systems

For navigation and radiocommunication systems, IEC 61162-460 or equivalent standards may be accepted in lieu of E27 section 4 security capabilities, if UR E26 is complied with. source source

The classification society verifies compliance during design, construction and commissioning, and the shipowner demonstrates it at annual and special surveys.

Design and construction

The systems integrator submits documents such as the vessel asset inventory and the ship cyber resilience test procedure to the Society and demonstrates compliance to it. source

Annual and special surveys

During the ship's operational life, the shipowner presents records or demonstrates implementation to the Society at the first and subsequent annual surveys and at special surveys. source

Equipment type approval

Type approval of computer-based systems under E27 is voluntary; systems with a valid type approval certificate covering E27 security capabilities may be exempted from survey by the Society. source

Enforced through classification: IACS societies apply the URs as class requirements and each member may set stricter ones.

Uniform implementation

Rev.1 of each UR is to be uniformly implemented by IACS Societies on ships contracted for construction on or after 1 July 2024. source

Minimum requirements

IACS Unified Requirements are minimum requirements; each member society remains free to set more stringent requirements. source

1. Standard UR E26 Cyber resilience of ships, Rev.1 Nov 2023 (complete revision)
2. Standard UR E27 Cyber resilience of on-board systems and equipment, Rev.1 Sep 2023
3. Guidance IACS Unified Requirements, UR E list
4. Guidance IACS UR E26 and E27 press release (revisions and 1 July 2024 application)

1. IEC 62443

   IEC 62443 is a general standards series for industrial automation and control systems; E26 and E27 are class requirements for ships and their on-board systems.

2. NIST CSF

   The NIST CSF is an outcomes framework for any organization; UR E26 groups class requirements for new ships under the same Identify, Protect, Detect, Respond and Recover headings.

Verified against official sources on 18 October 2026. We monitor the official sources for this framework. Watching since 22 September 2026. Subscribe to IACS UR E26/E27 (RSS)