The Concept of Space Shortage in Vessel Booking in International Shipping

Definition, Causes, Consequences, and Management Solutions for Iranian Exporters

In recent years, the growth of global trade volume, increasing dependence of companies on international supply chains, and ongoing fluctuations in the sea freight market have led many Iranian exporters to face challenges in the cargo transport process.

One of the key and relatively common challenges in sea carriage is the occurrence of Space Shortage or shortage of empty vessel space; an issue that may seem simple at first glance, but in practice can impact export planning, delivery times, and final sales costs. Given that a significant share of Iran’s exports relies on sea transport, an accurate understanding of the concept of Space Shortage, its causes, and strategies for mitigating it is essential for every exporter.

What Is Space Shortage?

Space Shortage is a term used in the shipping industry to describe a situation in which the available capacity of vessels is not sufficient for loading containers. In such situations, shipping lines cannot accept new bookings, or only allocate the limited space by imposing restrictions and higher rates (Premium). This issue becomes especially important when market demand for cargo transportation increases, but the number of vessels, container capacity, or the speed of loading and unloading does not meet market needs.

Put simply, when a shipping line declares Space Shortage, it means that—even if the exporter is ready to book—there is in fact no available space on the vessel, or space is offered only in limited quantities and at much higher costs. This phenomenon is usually seasonal or periodic, but sometimes occurs due to structural and long-term reasons.

In shipping industry terminology, Space Shortage refers to a situation in which the supply capacity of a shipping service is less than the registered demand for container booking. This shortage can result from vessels being full, a lack of empty containers, a canceled scheduled sailing (Blank Sailing), or even larger customers being prioritized by shipping lines.

In practice, when an Iranian exporter is faced with a “No Space” or “Space Subject to Confirmation” response, it means that even with cargo and documents ready, there is no guarantee of loading on the intended vessel. Under such circumstances, either the shipment time must be postponed to the next available service, or with additional payment (premium rate), limited space under the title “Premium Space” is purchased.

Especially in 2025 and 2026, the return of demand fluctuations on some Asian and regional routes and the concentration of major carriers’ fleets on more profitable routes has had direct impact on Iran’s access to global shipping capacity.

Main Causes of Space Shortage

A shortage of space on vessels is usually the result of a set of factors linked to the global supply chain. Recognizing these factors helps Iranian exporters to more accurately forecast market conditions.

1. Sudden Increase in Demand for Sea Freight

During periods of increased global export volume—such as during peak buying seasons at the end of the year or during global economic recovery—the demand for vessel capacity exceeds the ability of carriers. This is one of the primary causes of Space Shortage. Iranian exporters, especially in sectors such as petrochemicals, minerals, and FMCG, are more affected by these fluctuations.

2. Shortage of Empty Containers

Container shortage is a global challenge but is much more intense in the Persian Gulf region and on Iran’s trade routes. Sometimes empty containers accumulate in ports with little export demand, while export ports like Bandar Abbas face a shortage. This imbalance limits available capacity and results in Space Shortage.

3. Disruptions in Carrier Schedules

Delays in vessel arrival, blank sailings, reduced number of weekly services, or periodic maintenance of vessels directly impact available capacity. In the conditions of sanctions and operational restrictions, this is particularly tangible for Iranian exporters.

4. Port Limitations

If a port suffers from congestion, slow unloading or loading operations, or infrastructural limitations, ships prefer to change their schedules or reduce their stay. This reduces the practical loading capacity for exports and intensifies Space Shortage.

5. Sudden Changes in Fuel and Freight Costs

Rising fuel prices usually force carriers to adopt a more cautious approach in space allocation. In such cases, only customers who pay higher rates receive the limited available space.

6. Political and Geopolitical Conditions

Regional tensions, closure of shipping lanes, changes in port regulations, or insurance risks can also reduce carriers’ willingness and lead to space shortages.

Consequences of Space Shortage for Iranian Exporters

Space shortage in sea transport can have serious, multilayered consequences for Iranian exporters; consequences that sometimes not only increase costs, but also impact commercial credibility.

Delays in Cargo Dispatch

The first and most prominent result of Space Shortage is delay in cargo loading and dispatch. When the vessel has no capacity, the exporter must wait for the next service, which on some routes could mean one to three weeks of delay. This can lead to non-compliance with the agreed delivery time and weaken commercial relationships with foreign customers.

Increased Freight Costs

Carriers in periods of Space Shortage typically establish premium rates. This extra charge, either as a separate cost or as an increase in freight rate, raises the total export cost. Sometimes, freight for a single container may rise by as much as 50 percent.

Need to Change Route or Carrier

Occasionally, the exporter is forced to use longer alternative routes or different carriers instead of a direct service. This, in addition to increasing costs, also prolongs transit time.

Disruption of Production Planning

In large industries, production and export are coordinated in a chain. When shipping space is limited, the producer must adjust its schedule or store cargo in warehouses—an especially serious challenge for factories with limited warehouse capacity.

Reduced Competitiveness in Target Market

Since some competitors (for example, Chinese or Turkish producers) have greater access to carriers, the Iranian exporter in periods of Space Shortage may be less competitive in terms of delivery time and final price.

Structure of the Global Shipping Market and Iran’s Position

The global container shipping market is dominated by several major operators, including MSC, Maersk, CMA CGM, COSCO, and Hapag-Lloyd. These companies control more than half of the world’s container fleet capacity, and their decisions on ship allocation, adding or canceling services, and setting rates affect the entire market.

However, due to banking and insurance restrictions, Iran does not have direct and steady access to all these carriers. A large share of Iran’s container exports is carried via feeder vessels and subsequent transshipment in regional ports such as Jebel Ali, Sohar, or sometimes Karachi. This reliance on hub ports means that in times of capacity shortage, Iranian cargo is often a secondary or even tertiary priority.

In 2025 and 2026, major carriers have shifted focus to the Asia–Europe and Asia–North America routes. As a result, some fleet capacity has been relocated from the Persian Gulf to higher-demand routes, increasing pressure on the services relevant to Iran.

Macro Trends in 2025–2026 Intensifying Space Shortage

Imbalanced Demand Growth in Asia

In the second half of 2025, a surge in China’s exports to the Middle East and Europe led to faster-than-expected capacity utilization of many Asian services. Meanwhile, Gulf ports faced extra pressure due to increased re-export volumes and their regional hub role—this has indirectly affected Iran’s transshipment cargo.

Fleet Concentration on Main Routes

In 2026, major lines assigned a portion of their next-generation vessels to Trans-Pacific and North Europe routes. This has reduced the capacity of secondary services in the Gulf compared to the post-COVID peak. Even minor reductions are significant in restricted markets like Iran.

Ongoing Empty Container Imbalance

One structural market issue in 2025–2026 is unbalanced distribution of empty containers. Containers fill rapidly on the China–Europe and China–America trade lanes, but their return to some regional ports is delayed. In Bandar Abbas, exporters have sometimes faced shortages of 40-foot containers, effectively halting the transport process even before vessel booking.

Key Ports Related to Iranian Exports

Bandar Abbas; The Primary Pillar of Iranian Container Exports

Bandar Abbas remains Iran’s key container port, but its dependence on feeder services and lack of direct, major line calls reduces its practical capacity compared to competitors. During peak exports of petrochemicals and minerals, waiting time for confirmed space can increase to one to three weeks.

Further, any delay in feeder arrival at Bandar Abbas can impact the entire transshipment chain, since mother vessels in Jebel Ali or Sohar do not wait for Iranian shipments.

Jebel Ali; Main Hub but Highly Demanded

Jebel Ali is the region’s primary transshipment hub, with all major lines present. However, increased regional volumes and fierce competition for capacity in recent years have resulted in lower priority for smaller, indirect bookings. For Iranian exporters dependent on transshipment from this port, this means greater Space Shortage risk.

Sohar; An Emerging Alternative

Sohar Port in Oman has recently become an alternative for some regional shipments. Some lines use Sohar to ease pressure on Jebel Ali. For Iranian traders, routing via Sohar has sometimes shortened waiting times for loading space, though it is not always the most cost-effective solution.

Status of Key Shipping Lines for Iranian Trade

MSC

MSC, the world’s largest container operator, is active in the Gulf. Although it does not provide wide direct service to Iranian ports, transshipment is possible via its regional network. In periods of Space Shortage, MSC typically gives priority to contractual, high-volume customers.

CMA CGM

This carrier has a relatively extensive network in the Mediterranean and Middle East, and has sometimes shown more flexibility in handling transshipment volumes. However, at times of peak demand, premium rates in CMA CGM have increased significantly.

COSCO

For Iran–China trade, COSCO is especially important. Despite some operational restrictions, this line plays a vital role on Asian routes. In 2026, increased COSCO focus on China exports has meant regional, smaller shipments are more limited at times.

Maersk & Hapag-Lloyd

Direct presence of these lines in Iranian trade is more limited, usually operating via agents or transshipment. During Space Shortage, securing capacity from these operators is generally more difficult for Iranian exporters than with other lines.

The Impact of Space Shortage on Freight Costs (2025–2026)

Under capacity constraints, freight rates become dependent not merely on supply and demand, but also on the level of customer access to carrier networks. For Iranian exporters, real transportation costs typically include elements beyond the Ocean Freight: additional transshipment fees, higher THC in hub ports, and sometimes operational risk surcharges.

On some Asian routes, the difference between the Iranian exporter’s paid rate and the global market average in 2026 has reached about 20 to 40 percent. This is mainly due to the indirect shipping structure and limited carrier choices.

The Role of Sanctions in Intensifying Space Shortage for Iran

Although Space Shortage is a global phenomenon, its effects are more pronounced for Iran. Sanctions have reduced the number of active lines, imposed insurance limits and complicated financial settlements. Thus, even when the global market does not face severe shortages, available capacity for Iran may be limited.

In other words, “space shortage” for Iranian exporters sometimes occurs not because vessels are full, but due to a lack of operational options.

Likely Scenarios for 2026 to 2028

Based on current trends, three main scenarios can be envisaged:

First, continued fluctuations in Asian demand, which may lead to repeated Space Shortage periods.

Second, gradual entry of new vessels into the global fleet, which may alleviate some pressure.

Third, strengthening the role of regional hubs, such as Oman, which may create opportunities for Iran—if supported by careful logistics planning.

Practical Strategies for Iranian Exporters

In such conditions, risk management is especially important. Experience shows that early booking, long-term contracts with reputable forwarders, diversifying shipments among several lines, and flexibility in timing are effective tools to reduce the impact of Space Shortage.

Ongoing monitoring of services and obtaining updated information from carrier agents helps prevent costly, last-minute decisions. In a market where space can be filled within days, fast decision-making is a competitive advantage.

Management Solutions to Reduce Space Shortage Risk

Though Space Shortage cannot be fully prevented, exporters can significantly mitigate the risk through professional strategies.

Early Planning and Advance Bookings

One of the most effective solutions is making reservations earlier than usual. Exporters who book two to three weeks in advance have a higher chance of securing space—especially in peak seasons (September to January).

Signing Long-term Contracts with Lines or Reputable Forwarders

Annual or periodic contracts with professional forwarders or carrier representatives offer a better guarantee for securing space. Shipping lines usually give priority to customers with fixed volumes and long-term contracts.

Diversifying Transportation Routes

Using alternative routes—such as via the UAE, Oman or Turkey—can reduce the risk of space shortage at Bandar Abbas. Sometimes, indirect shipping, though longer, avoids prolonged stoppages.

Flexibility in Choosing Loading Time

Companies not bound to dispatch cargo at set dates are less vulnerable to Space Shortage. Flexibility in cargo preparation and loading time increases chances of using suddenly available slots.

Avoiding Shipments During Peak Season

Avoid exports during periods traditionally affected by heavy transport demand. If export in those periods is unavoidable, earlier planning is crucial.

Cooperating with Route-specialized Forwarders

Forwarders active on specific routes usually have stronger operational relationships with lines and better secure space for their clients during Space Shortage periods.

The Role of Iranian Exporters in Space Shortage Management

Since export conditions from Iran are impacted by infrastructural, political, and carrier limitations, exporters need a more proactive approach to managing this challenge. Deep familiarity with target markets, awareness of seasonal trends, using shipping forecasts and continuous relationships with forwarders are essential tools for better planning. Also, diversifying origin ports—such as utilizing Chabahar and Bushehr in addition to Bandar Abbas—can reduce pressure.

Some successful Iranian exporters even manage part of their container inventory through container leasing plans to avoid shortages in emergencies. Although this level of professional management is costly, for high-volume exports it is highly cost-effective.

Conclusion

Analysis of regional ports, the behavior of major shipping lines, and market trends shows that Iranian exporters must regard this phenomenon not as a temporary crisis but as a part of global market reality, organizing their strategies accordingly. Ultimately, success is ensured by a combination of analytical awareness, strong logistics networking, and forward-looking planning.

Space Shortage is one of the most important challenges in sea transport in recent years, and Iranian exporters are more affected by it than many other countries. Vessel capacity shortage, container shortage, demand fluctuations, port infrastructure problems, and carrier schedule disruptions are among the main factors intensifying this phenomenon. Consequences for Iranian exports include long delays, higher transport costs, rerouting, production planning disruption, and reduced competitiveness in target markets.

Nevertheless, exporters can significantly manage this risk by adopting strategies such as advance booking, long-term contracts, route diversification, using professional forwarders, and more precise planning. Ultimately, success in these conditions depends on a combination of foresight, agility, and effective communication with the logistics network.