America's 'Most Connected Airport' In 2025 Is A Bustling Midwest Gateway To Just About Anywhere

What does it mean for an airport to be well-connected? According to the Official Aviation Guide (OAG), a hub's connectivity depends on how many connections to domestic or international destinations it offers travelers.

According to the latest OAG report, Chicago's O'Hare International Airport is the most connected airport in the U.S. based on 2025 data and ranks No. 7 globally. Flyers can reach 214 domestic destinations, with a total of 297 if you include international options. The Midwest megahub has repeatedly topped OAG's rankings in recent years, often earning the title of America's most "well-connected" airport. 

It certainly helps that O'Hare International Airport is one of the largest airports in the country, covering more than 7,200 acres. The airport has 201 gates spread across its four terminals, most used by United, which is based in Chicago, and American Airlines. That's a lot of space for hundreds of thousands of travelers who pass through each month. In August 2025 alone, more than 8 million flyers moved through O'Hare.

Globetrotters from Chicago O'Hare International Airport can catch non-stop flights to cities such as Delhi (India), Tokyo (Japan), Istanbul (Turkiye), or to one of 190 U.S. cities. According to Fly Chicago, the airport offers over 1,000 daily flights to more than 170 U.S. cities, and another 118 daily flights to 60 international destinations. This breadth of service makes it easy for U.S. citizens to plan international trips if their closest airport doesn't offer flights to top vacation spots, whether they're planning a sunny beach getaway or a city break. 

Travelers love to be given options, but with greater connectivity comes greater complexity. As it turns out, O'Hare is one of the five U.S. airports with the most delayed holiday-season flights, though it's worth noting that the number of delays is significantly lower than at other hubs on the list, like San Francisco International Airport or Miami International Airport.

Still, serving millions of travelers is a big feat for Chicago's main airport, and it's not the only bragging right it's earned in 2025. The aviation industry is believed to be responsible for 2.5% of global CO2 emissions, and, to combat that, O'Hare has gone 100% carbon-free as of January this year. This required years of planning — and it certainly paid off. That doesn't solve all environmental challenges in the industry, of course, but the move positions the airport as a front-runner in the U.S. for sustainable air travel.