Just in Time Arrivals

This portal [intro text]

1. What is Just In Time Arrival?

The process of a port call nowadays is generally not optimized. Ships may “hurry” to the next port, only to find out that the berth is not available because e.g. another vessel is alongside, cargo is not available for loading, or no tank is available for discharging. This results in either having to “wait” outside the port at anchorages for many hours, days or even weeks, or manoeuvre at very low speeds in the port area while waiting for the availability of berth, fairway and nautical services. This “hurry up and wait” mode of ship operation has many disadvantages and from a safety, environmental and economic perspective can be improved significantly.

A vessel arrives Just in Time when it sailed to the port with the least amount of bunkers spend, but still arriving in time. This will save GHG emissions and will also reduce the anchor time at ports. These factors will have a positive impact on safety, environment and efficiency.

1.1. To be moved elsewhere...

An example of sailing JIT

To explain “JIT speed”, an example of a vessel sailing from Felixstowe (UK) to Bremerhaven (GER), a voyage of 300 nautical miles (NM) is used. In the actual situation the voyage had a duration of 21 hours. The vessel sailed 15 hours at 20 knots and then anchored for 6 hours. To calculate the JIT speed of this voyage, two numbers must be defined: the minimum speed of this voyage to arrive Just In Time and the most economical speed of the vessel.

To calculate the minimum speed for this voyage, a constant optimal speed is assumed. As the voyage is 300 NM and the total duration of the voyage is 21 hours, the minimum speed the vessel can sail and still arrive in time is 300/21= 14.3 knots.

The most economical speed of the vessel is defined as the most fuel-efficient speed on a per nautical mile basis. This speed is derived from the provided fuel tables, based on vessel size bin and draught. For this voyage the most economical speed is 10 knots.

Sailing the most economical speed of 10 knots is not an option as the vessel will arrive too late. There are only 21 hours available, but the vessel needs 30 hours to arrive. So, the most optimal way to sail this voyage from Felixstowe to Bremerhaven is by sailing 21 hours at 14.3 knots.

Another vessel within the same size bin and draught has 35 hours available to sail the same voyage. The most economical speed is still 10 knots, while the minimum speed to still arrive in time has changed to 300/35= 8.6 knots.

So JIT speed is the most economical speed for this voyage. That can be explained as the consumption per mile is lower at 10 knots compared to 8.6 knots. The most optimal way to sail this voyage from Felixstowe to Bremerhaven is by sailing 30 hours at 10 knots and anchor for 5 hours.

2. What are the benefits of Just In Time Arrival?


  1. Improved safety
  2. Reduced emissions and air pollutants
  3. Cost savings (for fuel and lube oil)
  4. Less hull fouling
  5. Better capacity planning – for nautical services, berth planning etc.
  6. Lower risk of piracy in affected areas

2.1. Improved safety (moved to icons roll-over)

According to EMSA’s report 2021“Annual Overview of marine casualties and incidents”, most accidents happen during or just before a port call. When sailing JIT, there is a reduced number of vessels close to ports, and as a result, increased navigational safety in port approaches and anchorages. Communication and clarity prevent last minute manoeuvres and increase the safety of the port call.

Distribution of marine casualties and incidents by location, based on statistics on marine casualties and incidents which: involve ships flying a flag of one of the EU Member States; occur within EU Member States’ territorial sea or internal waters as defined in UNCLOS; or involve other substantial interests of EU Member States.


2.2. Reduced emissions (moved to icons roll-over)

Through the application of JIT Arrival, emissions of GHG  and air pollutants can be reduced in a two-fold manner:

  1. for the ship voyage through the optimization of the sailing speed and hence more optimal engine efficiency resulting in lower fuel consumption.
  2. for the port area as time of ships manoeuvring in the approaches or waiting at anchorage is reduced.


A recent study commissioned by the Low Carbon GIA into the potential of Just in Time Arrivals in container shipping concluded that JIT Arrivals could result in an average CO2 reduction of 14.16% per voyage. When  applied to the last 24 hours of the voyage (i.e. optimization over the last 24 hours), savings are on average 5.90% per voyage. The last 12 hours can still save on average 4.23% per voyage.

3. How can JIT Arrival be implemented?

In order to understand how JIT Arrival can be implemented, it is important to first understand how a ship calls a port, and all the information is exchanged between the different actors. JIT Arrival requires strong triangular cooperation between the port authority, terminal and the ship, and will also require information and data exchange with other service providers within the port ecosystem (e.g. tugs, pilots, cargo services etc.)

The process how a ship calls a port is set out in the Port Call Business Process (see image below), which also lays out the data to be exchanged, at what stage and by whom.

The video below provides more explanation on the Port Call Business Process.

Whilst JIT Arrival is conceptually simple to understand, in practice it can be challenging to implement. The follow interactive image illustrates the simplified steps which a port can take to implement JIT Arrival. More detailed information can be found in the JIT Guide.

3.1. Drivers and motivation

Before implementation of JIT Arrival, it is important to understand motivation and drivers for all players…. (to be added to clickable diagram)

Add example of Newcastle for safety reasons. Top-down approach. Motivation for different players – win-win so there are incentives for each stakeholder – requires collaboration.

Could be safety, environmental – underpinning by potential studies such as calculation of emission potential.

Local potential

If a port wants to start calculating the potential in the own port, that can be done by using local data, if available. Also AIS data might be of use.

Table top exercise

Another way to get feeling by the impact Just in Time arrivals can have in a port, a table top exercise can be executed. After defining a local real life scenario, this scenario should be prepared and a meeting with all actors should take place to “play”. In this way (potential) barriers and (potential) benefits will become clear.

3.2. Identification of barriers

Barriers to JIT Arrival can broadly be categorized into contractual and operational barriers. Contractual barriers mainly apply to the ability of the data receiver to use the data. For example, the Master may not be able to adjust speed without being in breach of contractual clauses. Operational barriers refer mainly to the exchange of high-quality or reliable data between stakeholders in the port, and to and from the ship.

The following sections provide more information on the identification of barriers and potential solutions for the implementation of JIT Arrival.

3.2.1. Contracts

For ships on time charter the owner–charterer relationship is not a problem, as the charterer has the right to direct the ship to proceed at any speed. The charterer pays all the bunkers so directly profits from fuels savings.

Therefore, contractual barriers primarily apply to those ships that operate under voyage charter (i.e. most bulkers and tankers) during the laden voyage. This is because voyage charter parties include a Due Despatch clause which obliges the ship’s master contractually to proceed to the next port with utmost despatch, regardless of whether a berth is available or not.

An additional complication is added when a ship carries several different cargoes. For example, a parcel tanker may carry 20 or more different cargo parcels. Per parcel, multiple parties are involved in the commercial agreements e.g. seller, buyer, broker, charterer and shipowner, and the shipowner may have different obligations to different cargo owners.

Furthermore, cargoes may be traded many times between the load and discharge port. This means that each party in that sales chain must redraft the owner–charterer cargo contract after each trade agreement. Currently, there is no widely used industry standard clause for JIT Arrival that is included by default in the charter party (and widely accepted by all parties). On the contrary, several different clauses exist, e.g. BIMCO has published a Virtual Arrival Clause for Voyage Charter Parties and also shipping companies have developed their own clauses for JIT Arrival implementation that differ from the BIMCO clauses (e.g. SHELLVOY6 and BPVOY4). But since there is limited application of JIT and parties do not understand the liabilities JIT Arrival could potentially impose, every sales contract could take days to agree. By that time, the ship would have arrived at the discharge port, with no application of JIT Arrival.

Finally, even if contractually an agreement is sought for all cargoes and among all parties involved, how to calculate and share any costs/revenues from the implementation of JIT Arrival may be complex. For example, in a voyage charter delays due to the weather are paid by the shipowner whereas delays in the loading and discharging of cargo are paid by the charterer.

Potential solutions

Since the contractual barriers mainly relate to those ships that operate under voyage charter, potential solutions
mainly aim to improve existing voyage charter party agreements:
– Include a JIT Arrival standard clause in the voyage charter party to allow the ship’s Master to
optimize speed, without being in breach of contract
– Adapt charter party to allow the vessel to arrive at the Requested Time of Arrival at the Pilot
Boarding Place (RTA PBP) whilst tendering her NOR at the time that she would have arrived had
she proceeded on voyage at charter speed using due despatch (virtual arrival) and physically
arrived at the PBP
– Include a JIT Arrival standard clause in the charter party contract that can be passed through the
sales chain like any other clause. Standard clauses, since they automatically come into effect,
are normally not challenged by any party. Applying a standard clause does not mean that by
definition costs/benefits are fairly distributed, but the distribution is accepted, and no time is
lost in renegotiating terms
– For the calculation and sharing of the financial benefits of slowing down the ship, some charter
parties prescribe that the Virtual Arrival time (i.e. time the ship would have tendered its NOR
based on RTA PBP) must be determined by an independent third party which party should be
agreed upfront by both the ship owner and charterer
– Fuel savings could also include a split with terminal (in addition to the shipowner and charterer)
such that all three parties receive an equal share of the fuel saved through JIT Arrival. This requires
a check and adjustment of the entire contractual chain

Key Questions

  • Add questions:
  • Are there contractual barriers for the ships to optimize speed in order arrive JIT?
  • Are there…?

3.2.2. Operations and Procedures


Gaps in procedures

A major step that has to be taken before Just in Time can be implemented, is beside the data related gaps to identify the gaps in procedures in ports. Examples of gaps in procedures are:

-There is no preclearance by customs

-Not enough capacity or not aligned capacity of a (nautical) service provider

-Delays by terminals that are not ready with cargo operations at the vessel order time

-Extreme peaks and troughs in capacity demand


Key Questions

  • Add questions!

3.2.3. Data and Standards


Data exchange and therefore data sets and data standards are of great importance in the implementation of Just in Time arrivals.

This page considers how the exchange of the key information and data that is required for JIT Arrivals can be improved in a port.

As Just in Time Arrival relies on data of shipping lines, terminals and ports, digital exchange of data in an uniform way is of huge operational importance. In line with resolution MEPC.323(74), IMO invites Member States to encourage cooperation between the shipping and port sectors to contribute to reducing GHG emissions.

Data Sets

Non-technical vs. technical standards: Where non-technical standards are the definitions of the data elements, technical standards provide the way how these data elements can be exchanged. For example the API specifications.

Important data events for JIT

The most important timestamps for Just in Time arrivals are obviously related to the arrival of the vessel. As many vessels are on berth exchange, also the timestamps related to the outbound vessel are important. For a definition of the relevant timestamps, see endorsed standards.

Data mapping

To define the Just in Time arrival process in a port, it is important to map if all important timestamps are available and if these timestamps are according to the standards. Mapping where (or in which system(s)) the timestamps are available is also important. The last check should be to understand which systems are connected and are exchanging which relevant timestamps already.

The importance of standards

As discussed before, standards and the usage of standards is key in the successful exchange of data and thus in Just in Time arrivals.


For nautical, administrative and operational data sets and corresponding standards a implementation guide is available or under development. These can be of help while implementing Just in Time arrivals.


Gaps in data definitions

As discussed before, it is key to the process to speak the same language in a port and also between ports as shipping is a worldwide trade. So mapping the gaps between the current definitions used in port and the standards is important.

Gaps in availability of data

It could also be the case that some data is not available in a port, or that a timestamp is not used at the moment. To be fully aligned with the Just in Time concept, all timestamps should be in place.

Gaps in data exchange

As timestamps are available, it is important that these timestamps can be exchanged system to system between the relevant parties. If not all timestamps are shared between the relevant parties, these gaps should be identified.

Key Questions

  • Add key questions!

3.2.4. Stakeholders/Actors

The stakeholders

All parties involved in the arrival and departure* time of a vessel are important to make Just in Time work. The biggest players are:

  • port authorities
  • terminals
  • shipping companies
  • (nautical) service providers

Stakeholder mapping to the local situation

Key stakeholders in port in relation to Just in Time should be mapped. Basically, the Just in Time concept and the business process of port call optimization with “general” stakeholders should be translated to the local situation.

Data owners

An important group to involve are the parties that are data owner of timestamps that are relevant to the Just in Time process. For example, think of a terminal who defines the RTA Berth of a vessel.

Other stakeholders

Besides data owners also other parties that play a role in the Just in Time process or are key in the (decision making) processes in port should be involved. For example, if the Port Community System will be used for the data exchange, involve them.


Key Questions

  • Add key questions!

3.3. Action plan

Working towards “filling gaps”

After mapping all the gaps, the solution to fill these gaps should be brought up in an action plan, including timelines, project scopes, etc.

How to fill the gaps

For every gap a project plan should be made work towards solutions. As many gaps have local causes, solutions may differ for every port.

As an example, the following steps could be used to solve capacity constraints at a service provider:

1.Determine if there is a mismatch in the current situation. If there is no mismatch, no reason for further research. When there is a mismatch, further research on:

2.The scale of the mismatch: the difference between the desired capacity and the delivered capacity over time

3.The reason why the mismatch arises and further developments in time; which factors are the basis for this?

4.Which costs do occur because of the mismatch?

5.Which solutions are possible and who plays a role in these solutions?

6.What are the costs/investments for these solutions?

7.How could these costs be settled?


The Just in Time project plan

All gaps and solutions should be listed and worked out, this is the workplan or project plan that helps the port to work towards Just in Time arrivals implementation.

3.4. Implementation

The Just in Time project plan in action

When the project plan is finished, it is time for the implementation phase. In this phase a port executes the action plan. Dependent on why Just in Time arrivals is implemented, the current state of the port and the complexity of a port, executing the action plan can take up to several years.

Dependency on reason for  JIT implementation

As stated before, there are three main reasons why ports implement JIT. When the main reason is safety, often it is shown in ports that the implementation of JIT is done in a short period, because there is a clear need and the government is pushing this, for example in regulations.

When the environment or efficiency is the main reason, often the lead time is a longer as the government is not pushing JIT, but ports and/or actors in ports are pushing the implementation of JIT, which results generally in longer lead times.

Dependency on current state and complexity of the port

The current state and complexity of the port define in general how complex and how many actions should be taken in the project or action plan. The following related characteristics of a port might decide on the lead time:

Just in Time in other ports

Implementation of Just in Time is already done by several ports around the globe. Besides Just in Time, some ports implemented “virtual arrivals”. Virtual arrivals is close to Just in Time and also permits vessels to optimize the speed to the port of destination.

Interview / lessons learned Port X

Here you will find later an interview with Port X which implemented Just in Time arrivals.

Interview / lessons learned Port Y

Here you will find later an interview with Port Y which implemented Just in Time arrivals.

Relevant documents

For all data sets and corresponding standards a implementation guide is available:

Other relevant documents:

5. How can GreenVoyage2050 and the Low Carbon GIA support implementation?

Call for action

As mentioned before, implementing Just in Time arrivals is of major importance to reduce emissions and to increase safety and efficiency in ports. Therefore IMO highly stimulates ports to start implementing Just in Time arrivals.

IMO GIA’s role


IMO GV2050’s role

The IMO Greenvoyage 2050 goal is to initiate and promote global efforts to demonstrate and test technical solutions for reducing emissions, as well as enhancing knowledge and information sharing to support the IMO GHG reduction strategy.

The implementation of Just in Time arrivals is one of the key elements in this strategy.

IMO GV2050 can help

The IMO GV2050 team can help by explaining the standards, business process and Just in Time concept, or by providing examples of data mapping in other ports.


IMO GV2050 can help

The IMO GV2050 team can help by providing examples of gap mappings in other ports and by challenging the (un)defined gaps.

IMO GV2050 can help

The IMO GV2050 team can help calculating local potential based on global datasets / calculations and research and by helping them to provide a framework to come up with a local potential calculation.

The IMO GV2050 can also help by providing relevant materials like fuel tables and examples of previous table top exercises held in other ports.

Please reach out to us if we can be of any help in your Just in Time arrival implementation voyage!


IMO GV2050 can help

The IMO GV2050 team can help by explaining the business process and Just in Time concept, or by providing examples of actor mapping in other ports.

IMO GV2050 can help

The IMO GV2050 team can help by providing examples action plans in other ports and by challenging the defined action plan.