Heathrow Airport is investing billions to expand two terminals before formally proposing a third runway

Heathrow Airport is set to unveil a multi-billion-pound expansion plan to upgrade terminals two and five, laying the groundwork for a long-debated third runway. CEO Thomas Woldbye will announce the privately funded investment on Wednesday, which also includes reconfiguring the airfield and improving transport links.

The ambitious expansion comes after Chancellor Rachel Reeves threw her support behind the third runway last month, citing its potential to create 100,000 jobs and boost the UK economy. Woldbye is expected to highlight the economic benefits while also addressing environmental concerns, promising “strict safeguards” on noise, air quality, and carbon emissions.

In a strategic move to support British industry, Heathrow will sign a pact with British Steel to use UK-made materials for infrastructure projects, reinforcing domestic manufacturing at a time when US steel tariffs threaten the industry. The last major Heathrow project—Terminal 5, completed in 2008—required 80,000 tonnes of steel, hinting at the scale of what’s to come.

However, the expansion remains a divisive issue. Environmental groups, local authorities, and residents have long opposed Heathrow’s growth, arguing that increased flights would worsen pollution and disrupt communities. Legal and planning challenges could delay construction, with estimates suggesting it could take over a decade before the runway becomes operational.

Despite these hurdles, Reeves has set a bold timeline, pushing for construction to begin by 2029 and the runway to be operational by 2035. Woldbye has acknowledged the immense challenges ahead, calling the project one that will require “Churchillian resolve” to see through.

Heathrow, the UK’s largest airport, handled a record-breaking 83.9 million passengers last year, with its two runways operating at maximum capacity. Flights are currently capped at 480,000 annually, but a third runway could increase that limit to 720,000, solidifying Heathrow’s status as a global aviation hub.

As the formal planning process looms, Woldbye is set to reassure stakeholders that Heathrow is listening to concerns and committed to working with local communities. “This project can only go ahead if we meet the rules on noise, air quality, and carbon… it’s as simple as that,” he will say.

With trade worth £200 billion passing through Heathrow annually, the expansion carries significant economic stakes. Whether the project can overcome opposition and bureaucratic hurdles remains to be seen, but for now, Heathrow is pushing full speed ahead.