Southwest Airlines announced plans Wednesday to boost its presence at Phoenix Sky Harbor International Airport along with plans for a $40 million investment to expand its maintenance facility at the airport.

The Dallas-based airline committed to occupying a future eight-gate concourse at Terminal 4. The announcement was made by Southwest Airline’s President Tom Nealon with Phoenix Mayor Greg Stanton at a gathering of the PHX Aero Club.

The eight-gate concourse Southwest Airlines will occupy will be the eighth and final concourse at Terminal 4, and is scheduled to open in 2021. Southwest currently occupies three concourses at Terminal 4.

“We’ve never wavered in our commitment to serving Phoenix’s travelers,” Nealon said.”Our customers tell us they love the hospitality they receive at Sky Harbor and we’re looking forward to welcoming them into our new space when the new concourse opens in just a few short years.”

Southwest is adding a hangar and doubling the number of maintenance bays from two to four at the Phoenix facility with its $40 million investment.