The maritime navigation industry is entering one of its most important transitions in decades. The IMO’s transition to S-100–based ECDIS has raised practical questions across the shipping industry, particularly regarding regulatory timelines, system upgrades, and responsibilities for existing and newbuild vessels.

At Master Systems, we closely work with vessel operators in commercial shipping, offshore, and specialized fleets. We understand the confusion around S-100 regulations, especially regarding existing vessels versus newbuilds. 

What Is S-100?

S-100 is IHO’s new global hydrographic data model. This new framework serves as the foundation for next-generation navigational solutions. It will improve the accessibility, compatibility, and usability of hydrographic and marine data. The system enables multiple levels of navigational information to be displayed side-by-side simultaneously. The interoperability rules ensure that the layers interact with each other in a way that supports the marine activities while avoiding screen clutter. 

Various S-100 Datasets and Products

One of the differences between S-57 and S-100 is that S-100 is not a single chart format. It’s a framework supporting several standardized data products, which improves certain aspects of navigation. 

The following are the main S-100 products that are of most relevance to ECDIS and ship operations:

• S-101 – Electronic Navigational Charts (ENCs)
• S-102 – Bathymetric Surface
• S-104 – Water Level Information 
• S-111 – Surface Currents 
• S-124 – Navigational Warnings.    
• S-129 – Under Keel Clearance Management

This creates a safer navigation, reduces the workload on the bridge, and helps with better voyage decision-making. This is particularly important in shallow areas, ports with heavy traffic, and environmentally sensitive regions. 

S-100 ECDIS Regulatory Timeline: What Happens in 2026 and 2029

Despite these concerns, the International Maritime Organization (IMO) has established an acceptable and practicable timeline for the implementation of S-100 ECDIS. 

Let’s clarify the two dates that matter most.

From 1 January 2026 – Voluntary Usage Commences

• S-100 capable ECDIS may be installed and used legally.
• Type-approved S-100 ECDIS will be supplied.
• The use of S-100 data is Optional.
• S-57 ENCs can be freely used by ships without any limitations.

During this stage, shipowners are free from regulatory pressure to assess, test, and plan the introduction of S-100.

From 1 January 2029 – Mandatory for New Installations

From this date onwards, all new ECDIS systems need to be S-100 compliant

It Applies to:

• Refurbished vessels
• Retrofit or replacement ECDIS systems

The new ECDIS has to comply with the IMO performance standards. They apply only to new installations of ECDIS and shall not apply to ECDIS already installed. 

What About Existing Vessels?

One of the biggest concerns of the customers is about the existing ships. There shall be no requirement to replace existing S-57 ECDIS systems. The ships will continue using the S-57 ECDIS on condition that:

• The system is functional
• It complies with existing IMO performance standards

There is presently no deadline specified for the S-57 ENCs. This ensures a continuity of operations while giving the shipping fleet the flexibility to coordinate the upgrade with the dry-docking schedules. However,  the S-57 will eventually be phased out. The exact date has not been determined. 

What do shipowners do?

• 2026–2028 is a planning and transition window
• Newbuild contracts should already specify S-100 capable ECDIS
• Existing fleets should assess upgrade paths, but no immediate action is mandatory
• Early adoption can reduce long-term costs, training pressure, and operational risk.

If your vessel has many operational years ahead, planning an S-100 transition early reduces future cost, downtime, and compliance pressure.

Dual-Fuel ECDIS: The Practical Transition Solution

The modern S-100 ECDIS systems are designed as “dual-fuel” systems, which means they can display:

• S-57 charts (current standard)
• S-101 charts (new S-100 standard)

This allows vessels to:

• Use S-101 charts where available
• Seamlessly fall back to S-57 in other areas
• Operate globally without disruption

This dual ability is an essential one that comes into play during the period of transition, and it is one of the major designations recommended by Master Systems when it comes to advising on the upgrade of the fleet.

What Extra Benefits Does S-100 Bring to the Bridge?

S-100 doesn’t only deal with “compliance” – more fundamentally, it has some important operational benefits:

• Automatic water level adjustment (reduces manual tidal calculations)
• Enhanced safety contours using high-resolution bathymetric data
• Improved under-keel clearance awareness
• Navigational graphical warnings on charts
• Fewer false alarms and better management of alerts
• Lower cognitive load for bridge officers

These improvements directly support:

• Navigational safety
• Fuel efficiency
• Port and shallow-water operations
• Future autonomous and smart shipping technologies
  

Master Systems Role in the S-100 Transition

As a reliable source of marine navigation solutions, Master Systems helps vessel owners by:

• S-100 readiness assessments
• ECDIS upgrade planning
• New build navigation system integration
• Crew familiarisation guidance
• Long-term compliance strategy
  

Our focus is simple: it includes safe routing, regulatory certainty, and future-proof ships.

Conclusion 

S-100 is not a disruption; it’s an evolution. Ship owners who understand the timeline and plan early will benefit from better safety, smarter navigation, and easier regulatory compliance.

If you need clarification on precisely how S-100 impacts your particular vessel or fleet, then Master Systems is ready to walk you through it. Contact Master Systems for your ECDIS update. 

Frequently Asked Questions (FAQs)

1. Is S-100 ECDIS mandatory right now?

No, S-100 ECDIS systems are not mandatory at present. However, starting from 1 January 2026, S-100 compliant ECDIS systems will be allowed to be fitted and used optionally, provided that the systems are approved. Mandatory usage will only begin from 1 January 2029.

2. Will existing ships need to upgrade the present ECDIS installed in them by the year 2029?

There is no need to upgrade the existing S-57-based ECDISes by the end of 2029. The provision applies only to new ECDISes that will be installed after this date. The existing ships are free to operate with their present systems until further notice by the IMO.

3. Will S-57 charts expire in the year 2029?

No, S-57 ENCs will remain supported in the foreseeable future. Although S-57 will be phased out, it is not known at this time on what specific timeline. During this transition period, both S-57 and S-101 charts will remain in use.

4.  Is this requirement of 2029 also for retrofits?

Yes, from 1st January 2029 onwards, all new ECDIS system installations, whether replacing existing systems or retrofitted, must comply with S-100. And this applies even if the ship is not a new ship.

5. Are newbuild vessels delivered before 2029 required to have S-100 ECDIS?

No, new installations are still able to use S-57 ECDIS before 1 January 2029. However, owners with new installations are now preferring the installation of S-100-ready ECDIS.