The 2008 merger of Delta Air Lines and Northwest Airlines, unluckily on the eve of the global financial recession, is the largest airline merger in history, more than twice the value of the proposed Irish-led takeover of Easyjet by Castlelake,
But when it comes to Europe it is a different story. Here is a list of the most significant airline M&A deals in history, focused on value and industry impact:
- Delta Air Lines + Northwest Airlines (2008) — Approximately $17.7 billion combined enterprise value (often cited in the $11-18 billion range depending on metrics). This created the world’s largest airline at the time by passengers and fleet size.
- American Airlines + US Airways (2013) — $11 billion (plus assumption of debt). This formed the world’s largest airline and solidified the US “Big Three” (American, Delta, United).
- United Airlines + Continental Airlines (2010) — Approximately $3.5-6.8 billion (merger of equals with significant enterprise value). Created a major global network carrier.
- British Airways + Iberia (2010/2011) — Proposed and guided by Willie Walsh, approximately $8.6 billion equivalent in enterprise value, forming International Airlines Group (IAG).
- Lufthansa + Swiss International Air Lines (2005) and other European deals — Values in the multi-billion range, though often lower than US mega-mergers.
- Other notable deals include JetBlue’s attempted acquisition of Spirit Airlines (~$3.8 billion, blocked), Alaska + Hawaiian (~$1.9 billion), and various smaller or failed attempts.
EasyJet’s proposed takeover by US investment firm Castlelake (announced/agreed in principle in July 2026) values the airline at approximately £5.5 billion (~$7.3 billion).
This places it among the top 5-7 largest airline deals in history by headline value — comparable to or exceeding several major legacy mergers in nominal terms. It stands out as one of the largest take-private deals for a major European low-cost carrier and ranks as one of the biggest in European aviation M&A. It is smaller than the Delta-Northwest and American-US Airways deals but larger than many other high-profile transactions.
Exact rankings can vary depending on whether one uses equity value, enterprise value, or inflation-adjusted figures, and many deals involved significant debt assumptions. US legacy carrier consolidations in the late 2000s/early 2010s dominate the upper ranks due to the scale of the American market. EasyJet’s deal, if completed, would represent a major shift toward private equity ownership in the low-cost sector.
