Vietnam has overtaken Thailand to become Southeast Asia's second-largest aviation market in July 2026, with 7.4 million seats (+5.6% YoY), while Thailand dropped to third with 6.9 million seats (-3% YoY). The shift reflects broader regional capacity contractions driven by Middle East geopolitical tensions and elevated fuel costs, forcing Southeast Asian carriers to reduce international routes. For Thai SMEs in aviation, logistics, and tourism, this signals competitive pressure and potential demand headwinds.