Aer Lingus is the ninth-largest operator between Europe and the US by passenger numbers. According to the country’s Department of Transportation (DOT), the Irish flag carrier transported 2.8 million passengers in this market between February 2025 and January 2026. Compared to the prior 12 months, traffic rose by 5.1%, which was nine times more than for the entire Europe to US market (0.6%).

New routes from Dublin Airport (DUB) to Denver (2024), Indianapolis (2025), Las Vegas (2024), and Nashville (2025), along with a return to Minneapolis (2024), have contributed to this development. Figures for 2026 will be impacted by Aer Lingus ending all long-haul flights from Manchester, counterbalanced by the launch of services from DUB to Raleigh/Durham and Pittsburgh.

Aer Lingus’ US Route With The Lowest Load Factor

Credit: Airbus

Using DOT data to examine all the carrier’s US services identifies the markets with the lowest loads. As always, load factor (technically, seat factor) is just one performance measure, and it should not be considered in isolation. Do not read too much into it; it is always about how it is achieved. Usually, exploring the broader context helps to explain it.

With only 62.6% of seats filled, DUB to Minneapolis is the worst-performing route in this sense (59,233 round-trip passengers). This market was originally part of Aer Lingus’ network from July 2019 to April 2020, when Boeing 757s, leased from Air Contractors, were deployed. The route returned in April 2024, initially on the Airbus A330-200, but since then on the A321XLR.

When flights to Minnesota returned, Aer Lingus served the market on a seasonal basis only. However, flights now run year-round, perhaps driven by Delta Air Lines’ launch of Minneapolis-DUB flights in May 2024. This situation has created overcapacity, particularly in the winter, as both airlines operate during the off-season.

While Aer Lingus has fewer departures during the winter than in the summer, operating during the cold period mainly explains the poor load. For example, the carrier only filled between 48.9% and 52.3% of seats between November 2025 and January 2026. However, while the summer obviously did better, it was not overly great, as no month exceeded 80.1%. Expect changes. While not a like-for-like comparison, Frankfurt to Minneapolis had Lufthansa’s lowest US load factor.

The 2nd To 5th-Lowest Loads

Credit: Aer Lingus

With just 63.9% of seats filled, the DOT indicates that DUB to Denver had the second-lowest result (59,047 passengers). Cirium Diio data shows that Colorado’s capital and most populous city joined Aer Lingus’ network two years ago, in May 2024.

Unlike flights to Minneapolis, those to Denver run seasonally, with both the A330-200 and A330-300 deployed in the 12 months to January 2026. Despite this, no month did well, with loads varying from just 36.7% in March 2025 to 73.9% in June.

The route’s load fell by ten percentage points year-over-year as Aer Lingus increased flights from four weekly to six weekly. There is always a balance between demand, capacity, loads, fares, yields, competitiveness, market share, and so on. They do not exist in isolation. Change one thing, and the others will change too.

In third place was DUB to Miami with 69.3% (28,516 passengers), followed by DUB to Las Vegas with 70.1% (33,564 passengers) and DUB to Hartford with 70.3% (67,160 passengers).

The route to Hartford does not operate entirely on a year-round basis. There are virtually no flights in January and none in February, which is a very sensible decision. Despite deploying the relatively low-capacity A321LR and XLR, operating at a high frequency during the summer (daily) meant the loads were especially high. The best month was August (79.8%).

Aer Lingus’ 6th To 10th-Lowest US Loads

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With a load factor of 72.5%, the DOT shows that DUB to Indianapolis was sixth (37,076 passengers), followed by DUB to Los Angeles with 73.2% (145,269 passengers), DUB to San Francisco with 73.6% (154,264 passengers), DUB to Washington Dulles with 73.7% (176,844), and DUB to Philadelphia with 73.8% (78,116 passengers).

At the article’s start, it was stated that Aer Lingus transported 2.8 million passengers to/from the US. Some 83% of the traffic involved DUB, while Manchester had 10% and Shannon had 7%. Manchester had the highest overall load factor (a still fairly low 79.0%), followed by Shannon (78.2%) and DUB (75.7%). The carrier’s load factor from the Irish capital has fallen over the years, influenced by a growing number of thinner routes with more flights during the offseason.