Now that the peak summer is here, airlines are launching or restarting very few routes. Just a smattering of links involving the US will commence in August. Southwest Airlines, for example, will begin just four, all of which will take off this week.

Cirium Diio data shows that Southwest will have 3,817 daily movements (takeoffs/landings combined) in August. Its offering has risen from 3,761 daily services last August. While that’s a modest increase of 1.5%, it is from an enormous base. 906 routes are now scheduled: 844 domestic and 62 international.

These Southwest Routes Begin This Week

Credit: Wikimedia Commons

The following four links were all revealed last November. They all involve California on at least one part of the route. Two of them are from Long Beach Airport (LGB), which is renowned for a lack of slots due to being strictly limited. This situation is influenced by the airport’s location and noise restrictions. Southwest has increasingly scooped up the slots as more became available.

Southwest has only operated one of the four routes before, which is LGB to Portland International Airport (PDX). The airline had limited flights in both 2023 and 2024. The US Department of Transportation (DOT) shows that Southwest only filled 65.0% of seats on them. Much better results will be expected this time. JetBlue flew to PDX between 2008 and 2020, when the carrier pulled out of LGB. Alaska Airlines served LGB-PDX in the 1990s and again from 2009 to 2014 in retaliation to JetBlue’s entry. This led to relatively low fares and poor performance.

In the 12 months to April 2026, the DOT shows that 22,400 round-trip passengers flew indirectly between LGB and PDX. That was despite nonstop flights to PDX being available from Hollywood Burbank Airport (BUR), Los Angeles International Airport (LAX), Ontario International Airport (ONT), and John Wayne Airport (SNA).

Of course, the number of people traveling from LGB’s catchment to PDX is much higher than the 22,400 figure suggests, as it does not include leakage to other LA airports. Southwest is aiming to capture some of this traffic, and nearly all of it will be local. Not many people will travel on another flight elsewhere.

LGB To SEA Will Get One & Then Two Airlines

Credit: Wikimedia Commons

LGB last had flights to SEA in 2020, when JetBlue operated. The carrier served this market for 12 years. Alaska Airlines operated in the 1990s and returned in 2003 and existed on the route, and at LGB, until 2015. It pulled out and consolidated at other airports in the vast LA Basin. From 2009, Alaska deployed the CRJ700 operated by SkyWest. The oneworld member no longer uses that equipment.

LGB-SEA has been unserved for six years. With 23,800 round-trip passengers in the 12 months to April 2026, excluding passengers leaked to other LA airports, SEA was LGB’s third-largest unserved market. Now it’ll be in the hands of Southwest (from August 4) and, not to be outdone, Alaska (from September 8). Alaska will run twice-daily, particularly on the 178-seat 737-900ER. It’ll be a far cry from when the CRJ700 was deployed.

Alaska will return to LGB for the first time in 11 years. This is clearly influenced by Southwest’s entry on the route to Alaska’s top hub. Nonetheless, Southwest has never had much of a presence between Southern California and the Pacific Northwest. In August 2026, the carrier only has 1.7% of the available departures, which is barely more than Allegiant Air. As Alaska is very much first (46.3%), the airline does not want Southwest to get much of a foothold from LGB to SEA. This is part of the increasing head-to-head competition between the carriers, which also now includes SAN to SBA and BUR to HNL.

A Quick Look At Southwest’s August Activity

Credit: Wikimedia Commons

Recall that Southwest plans 3,817 daily movements and 906 routes in August. In this peak summer month, the airline will serve 120 airports, including 106 within the US and the country’s territories in the Caribbean. Compared to the same month a year ago, Anchorage, Knoxville, Santa Rosa, St. Maarten, and St. Thomas are now served. However, the airline has ceased flying to Chicago O’Hare and Washington Dulles.

With an average of 491 daily movements, Denver International Airport (DEN) remains Southwest’s top airport. Harry Reid International Airport (LAS), serving Las Vegas, is second (459 daily), followed by Chicago Midway International Airport (MDW; 422 daily).