Cargo volumes at London Heathrow grew 5 percent, a figure that underscores how Europe's busiest airport continues to expand its freight throughput even as its runway infrastructure remains fixed at two.

Heathrow handles the overwhelming majority of its air freight in the belly holds of passenger aircraft rather than in dedicated freighters, a structural reality that ties cargo capacity directly to airline scheduling decisions and slot allocation. A 5 percent increase in volume therefore signals not just stronger trade demand but also more widebody activity — or fuller bellies — across the airport's long-haul network.

Why does a 5 percent rise matter?

Heathrow operates at effectively full capacity, with its two runways allocating slots to carriers under the airport coordination regime run by ACL, the independent slot coordinator. Cargo growth at a slot-constrained hub cannot come from simply adding flights. It comes from three levers:

• Higher load factors in existing belly-hold space
• Airlines up-gauging to larger widebody aircraft such as the Boeing 777 and Airbus A350
• Denser consolidation by freight forwarders competing for limited capacity

Each of those levers has cost consequences. When belly capacity tightens, forwarders pay more, and shippers of time-sensitive goods — pharmaceuticals, aerospace components, high-value electronics — absorb the difference or route via rival gateways such as Frankfurt, Amsterdam or Liège.

What does this mean for carriers and forwarders?

For the carriers that dominate Heathrow's long-haul schedule — British Airways, Virgin Atlantic and a roster of Gulf, Asian and North American operators — belly-hold freight has become a material revenue line on routes where passenger yields are volatile. A 5 percent volume increase suggests cargo sales teams are extracting more from the same airframe hours.

For forwarders, growth at a constrained hub raises the stakes on allocation agreements. Capacity secured a year ago at contracted rates becomes more valuable when spot demand pushes utilization higher, and the major integrators and forwarders — DHL, Kuehne+Nagel, DSV and their peers — will factor Heathrow's tightening supply into their winter and spring procurement rounds.

The figure also carries weight for the airport itself. Heathrow's operator has argued for years that a third runway is economically essential, and freight performance is part of that case. Cargo throughput growth strengthens the argument that the UK's premier gateway is leaving trade volume on the table because it cannot add flights.

How does the growth fit the wider market?

A single-hub figure must be read against the global air cargo cycle. Belly capacity industry-wide has recovered and in many markets exceeded pre-2020 levels as widebody fleets returned to long-haul routes, which has depressed freighter utilization and pressured rates. Growth at Heathrow against that backdrop indicates genuine demand strength into and out of the UK market rather than a capacity-driven statistical rebound.

The UK's trade mix supports that reading. High-value, time-critical exports — pharmaceuticals, specialty chemicals, luxury goods — and inbound e-commerce flows are precisely the cargoes that route through Heathrow rather than through sea or road-sea combinations. A 5 percent increase points to both export demand and continued e-commerce import growth through the southeast of England.

What comes next?

The test for Heathrow is whether cargo growth can continue at a hub that cannot add movements. If the 5 percent trend holds, expect sharper competition for belly allocation, more up-gauging in airline fleet decisions on Heathrow routes, and renewed pressure on policymakers to resolve the airport's expansion question — because at a two-runway hub, every additional tonne of freight has to fit on an aircraft that is already scheduled.