Global airline capacity exhibits mixed trends and fluctuating frequencies in September 2025

The latest data from OAG reveals a dynamic and mixed landscape for global airline capacity in September 2025. While overall capacity is forecast to be ahead of last year, at 515.1 million seats, a closer look shows significant regional variations and differing strategies among the world’s top airlines. This figure is notably lower than the July peak of 559 million seats.

Airline Frequency Growth and Contraction

Among the Top 20 airlines, United Airlines continues its aggressive growth strategy, adding the most extra frequencies with 6,900 more flights compared to September 2024. Delta Air Lines follows closely, increasing its frequency by 5,500.

In terms of growth rate:

• Turkish Airlines demonstrates the fastest growth this month, with an impressive increase in capacity.
• Conversely, Azul Airlines saw the most significant reduction, down $9.2\%$.
• A major change in trend was observed with IndiGo, which is now reducing flying compared to last year ($-0.5\%$), a reversal of its strong growth earlier in the year.

Regional and Domestic Market Capacity Shifts

Domestic markets showed varied performance globally. While countries like Indonesia, Japan, India, and the USA saw domestic capacity contract, strong growth was reported elsewhere.

Regionally, Central Asia continues to lead in growth among IATA regions, up $12.1\%$ year-on-year. All four African regions are also expanding, with Southern Africa seeing the highest growth at $10.3\%$.

In contrast, three regions experienced a decline in capacity:

• Caribbean: Down $3.4\%$ (the most significant decline).
• Upper South America: Down $2.7\%$.
• North America: Down $0.4\%$.

Largest and Fastest-Changing International Markets

The international market continues to be dominated by the route between Spain and the UK, which remains the largest with 5.6 million seats this month. This market is over 2.3 million seats larger than the second largest, the Germany–Spain market (3.2 million seats).

The Top 20 international markets experienced notable shifts in growth:

• The highest growth rate was recorded for the Chinese Taipei–Japan market, soaring $17.6\%$ year-on-year.
• This was followed by China–Japan (+$13.9\%$) and Germany–Turkiye (+$11.7\%$).

Conversely, the Canada–USA market showed the largest rate of decline at $-8.2\%$, reflecting airlines’ capacity reductions due to weakening demand. Other declining markets include France–Italy ($-2.9\%$) and Germany–Spain ($-2.1\%$).