Cristian Roldan was selected for his soccer ball juggling skills from 110 kids who tried out for the commercial.

On September 18, 2010, Blaise Nkufo scored the first three goals of his Major League Soccer career to help the Sounders beat the Columbus Crew 4-0. Nkufo, playing his sixth MLS game, scored on a rebound in the fourth minute, struck again in the 39th, and completed the hat trick in the 75th.

The team's ownership revealed the first Sounders jersey on May 28, 2008, and announced Microsoft as the team's sponsor in a five-year deal worth approximately $20 million. As part of the agreement, Xbox branding appeared on the front of the Sounders' jerseys and throughout the stadium, beginning with the Xbox 360 and Xbox Live and later replaced with the Xbox One. The jersey was modified several times to include promotions for Xbox games, including Halo 5 and Gears of War 4, before being replaced by Zulily in 2019.

Sigi Schmid was introduced as the club's first head coach on December 16, 2008, after leaving the Columbus Crew following their MLS Cup victory. From 2009 to 2016, Schmid led the Sounders to seven playoff appearances, four Lamar Hunt U.S. Open Cup titles, and an MLS Supporters' Shield.

In 2019, after going nearly a decade without an official mascot, Seattle introduced Sammy the Sounder--a young orca who loves to dance, hang with friends, and play soccer, just like his Rave Green ancestor, the original USL Sammy.

Fredy Montero (2009), Mauro Rosales (2011), and Nicolás Lodeiro (2016) all won MLS Newcomer of the Year.

The club set a state record for attendance at a soccer match on August 5, 2009, when 66,848 attended a friendly match with FC Barcelona, a record which was later broken when they hosted Manchester United in front of 67,052 fans, and broken again in the 2019 MLS Cup against Toronto FC with 69,274 in attendance.

In 2014, Clint Dempsey was named as captain of the 23-man United States squad ahead of the FIFA World Cup. On June 16, he scored against Ghana 29 seconds into the group play match. It was the fastest goal in American World Cup history, and fifth fastest goal in all-time World Cup history. With this goal, Dempsey also became the first American player to score in three consecutive World Cups.

On September 2, 2009, the Sounders became the second MLS expansion team in league history (Chicago was the first) to win the U.S. Open Cup in its first season. They did so by defeating D.C. United 2-1 on the road at RFK Stadium.

On 22 April 2011, a harsh challenge by Brian Mullan led to Steve Zakuani fracturing his tibia and fibula three minutes into a game against the Colorado Rapids. He was airlifted to hospital and underwent surgery the same day. Although doctors feared that his leg would have to be amputated because of compartment syndrome, Zakuani returned the following season, but he never regained his form, scoring only one goal over the next three seasons, and retired in 2014 at the age of 26.