Chicago-based United Airlines has determined that Boston was its most popular destination among its extensive domestic network. The carrier’s domestic operation in the New England city has not changed much since last summer. However, it has since pulled its only international route from Boston, leaving its service to connect solely to all seven of its US-based hubs.

Despite losing one route, the airline expanded by nearly 20 flights compared to last summer. The smallest of the big 3 United confirmed that it carried a record-breaking 48 million passengers this past summer in its Summer Travel Receipt, obtained by aviation geek Jason Rabinowitz on Friday. It considered Boston Logan International Airport (BOS) its most popular domestic airport throughout the season, although the date periods or range of months are not exactly clear.

The carrier’s network is smaller than that of its two legacy competitors, American Airlines and Delta Air Lines. The former, along with its regional brand American Eagle, offers regularly scheduled service to 21 destinations. Atlanta-based Delta – which operates a hub at BOS – has the largest network, with service to more than 50 destinations.

What’s the metric? Nonetheless, United’s network was reportedly robust compared to that of its other domestic destinations. Leslie Scott, United’s Managing Director of Global Response and Corporate Communications, told Rabinowitz that the metric determining the statistic is the exclusion of its hu.