Air cargo is any goods or materials transported by aircraft. It covers everything from small parcels to multi-ton industrial shipments, moving on dedicated cargo planes or in the belly holds of passenger flights. Though air cargo accounts for less than 1% of global trade by volume, those shipments tend to be perishable, high-value, or time-sensitive, collectively generating around 35% of world trade value. That outsized economic footprint is what makes the industry so significant despite its relatively small physical share.
Air Cargo vs. Air Freight
The two terms are often used interchangeably, but they refer to slightly different things. “Air cargo” refers specifically to the goods being shipped. “Air freight” is the broader process of getting those goods from point A to point B, including logistics services like documentation, packaging, customs clearance, and tracking. In practice, you’ll see logistics companies use “air freight” when describing the full-service transportation solution they offer, while “air cargo” appears more often when the focus is on what’s actually inside the aircraft.
What Gets Shipped by Air
Air cargo splits into two broad categories: general cargo and special cargo. General cargo is anything that doesn’t require unusual handling. Think electronics, machine parts, clothing, pharmaceuticals, and e-commerce packages.
Special cargo requires specific handling procedures and regulatory compliance. This category includes live animals, perishable goods (fresh seafood, cut flowers, vaccines), time-sensitive and temperature-controlled products, hazardous materials, and human remains. Each type is governed by detailed standard operating procedures and country-specific regulations. Dangerous goods, also called hazardous materials, face particularly strict rules. The FAA notes that anything added to an aircraft introduces risk, and improperly declared hazardous materials have contributed to catastrophic incidents.
Nearly 99% of world trade by weight consists of low-value bulk commodities like oil, metal ores, and grains that travel by ocean. Air cargo fills the gap where speed or careful handling matters more than cost per kilogram.
How Air Cargo Moves From Sender to Recipient
A shipment’s journey involves far more steps than loading boxes onto a plane. The International Air Transport Association breaks the full process into five categories of activity: origin forwarder, origin carrier, transport carrier, destination carrier, and destination forwarder. Altogether, these span 19 main processes and 78 sub-processes.
In simplified terms, the sequence looks like this. A freight forwarder receives the shipper’s request and checks the security status of the goods. They plan the routing, book capacity with an airline, arrange pickup, and collect the freight. Once the shipment reaches the origin airport, the cargo handling agent assigns an unloading slot, verifies piece counts against the electronic air waybill, and screens everything through x-ray and explosive trace detection. A build-up plan determines which cargo goes on which flight, and the shipment is loaded into standardized containers called unit load devices (ULDs). Those ULDs move to a secure holding area, then to the aircraft ramp for loading.
At the destination airport, the process reverses: unloading, security checks, customs clearance, and handover to the destination freight forwarder or directly to the recipient. Temperature-controlled and dangerous goods receive special attention at every stage.
Cargo Planes vs. Passenger Belly Hold
Air cargo flies two ways. Dedicated freighter aircraft, like the Boeing 747F or 777F, carry nothing but cargo. These planes can handle oversized, heavy, or irregular shipments that wouldn’t fit in a passenger aircraft’s lower hold. The second option is belly cargo, which fills the space beneath passenger cabins on scheduled commercial flights. On many routes, belly capacity is the more cost-effective choice for smaller shipments because the airline is already flying that route for passengers.
The balance between these two modes shifts with market conditions. During the COVID-19 pandemic, the grounding of passenger flights dramatically reduced belly capacity, and freighter aircraft took on a much larger share of total air cargo volume. Under normal conditions, the split is more even, with both channels playing complementary roles across different trade lanes.
How Shipping Costs Are Calculated
Air cargo pricing hinges on a concept called chargeable weight. Carriers compare two numbers: the actual weight of your shipment on a scale and its dimensional weight, which reflects how much space the shipment takes up. The chargeable weight is whichever number is higher.
To calculate dimensional weight, you multiply the length, width, and height of the shipment (in centimeters or inches), then divide by a standard dimensional factor that varies by carrier and trade lane. A large but lightweight box of foam padding, for example, might have a dimensional weight far exceeding its actual weight, so you’d be charged based on volume rather than mass. This system ensures airlines are compensated fairly for cargo that fills up space without adding much tonnage. If you’re shipping something dense and compact, actual weight will likely determine your cost. If you’re shipping something bulky and light, dimensional weight takes over.
Market Size and Major Carriers
The air cargo industry set a new volume record in 2024, surpassing the previous year’s levels by 11.3% and exceeding the previous high set in 2021. The market is dominated by a mix of integrated express carriers and airline cargo divisions. FedEx and UPS lead the pack as integrated operators that control the entire chain from pickup to delivery. Among airline cargo divisions, Qatar Airways Cargo, Emirates SkyCargo, and Korean Air Cargo consistently rank near the top in freight tonne-kilometers. Other major players include Atlas Air, Turkish Cargo, Cargolux, DHL, Cathay Cargo, Lufthansa Cargo, and Singapore Airlines Cargo.
Environmental Impact and Sustainable Fuel
Air transport is one of the most carbon-intensive ways to move goods. The primary tool available right now for reducing those emissions is sustainable aviation fuel, or SAF, which produces fewer greenhouse gas emissions than conventional jet fuel. SAF can be made from waste oils, agricultural residues, and other non-petroleum feedstocks, and it works in existing aircraft engines without modification.
The challenge is scaling production and spreading the cost. A collaboration between the Smart Freight Centre and MIT’s Center for Transportation and Logistics developed guidelines for “insetting,” a system where companies across the aviation supply chain share the cost premium of SAF rather than leaving it solely with airlines. These guidelines also establish standardized methods for tracking and reporting the emission reductions that SAF delivers, so companies can credibly account for their environmental impact. Adoption is still in its early stages, but the framework is designed to accelerate investment in SAF production and make decarbonization a shared responsibility across the logistics sector.