Top US-Europe flight routes achieve high seat occupancy rates

According to the US Department of Transportation, approximately 77 million passengers traveled between the United States and Europe in the year leading up to November 2024. This figure represents over 30% of international travelers from the US. During this period, more than 37 airlines operated over 500 routes connecting over 340 airport pairs, achieving an average seat load factor of 83%.

An airline's seat load factor is a measure of how much available capacity is utilized by passengers or revenue passenger miles. If there is too much capacity compared to demand, fares may decrease while load factors increase. Conversely, if capacity is insufficient for demand at a given price point, fares might rise while load factors drop.

In an analysis of over 500 routes during this timeframe, ten routes were identified as having the highest load factors. These routes were predominantly point-to-point and focused on leisure or visiting friends and relatives traffic. Notably, three of these routes offered only weekly services, benefiting from limited capacity and specific demand characteristics.