[8] It was also the first season at their new headquarters and training facility, the Sounders FC Center at Longacres in Renton, which opened in February 2024 and replaced the Starfire Sports complex in nearby Tukwila.

[9] The team was expected to undergo major roster changes after the expiration of contracts for key players according to Craig Waibel, who entered his second year as general manager.

[15][16] On December 4, 2023, the club announced that they would retain 22 players from the 2023 roster and declined the contract options for backup goalkeeper Stefan Cleveland, midfielder Ethan Dobbelaere, and forward Héber.

[18] The Sounders selected three players in the 2024 MLS SuperDraft, including two from colleges in the Pacific Northwest, and acquired defender Jonathan Bell in the Re-Entry Draft.

[21] With the return of Danny Leyva from his loan to the Colorado Rapids, the Sounders entered preseason with three young center midfielders who would compete to play alongside João Paulo.

[22] On January 24, the team announced the signing of Argentinian forward Pedro de la Vega to four-year Young Designated Player contract—the first in Sounders history.

[29] The first match of the season, against MLS Cup runners-up Los Angeles FC, was played on the road due to the installation of new FieldTurf at Lumen Field.

[13] The Sounders traveled without several injured starters, including goalkeeper Stefan Frei, defender Yeimar Gómez Andrade, and midfielder Albert Rusnák.

The team played with a modified two-forward formation and conceded two goals by the 55th minute; back-up goalkeeper Andrew Thomas made four saves in his debut.

Pedro de la Vega scored from a penalty kick in the 72nd minute that was awarded by the video assistant referee for a foul on Jordan Morris; the match ended in a 2–1 loss for Seattle.

[32] Pedro de la Vega left early in the second half with a right hamstrung injury, which the Sounders later announced would prevent him from playing for six to eight weeks.

[33] The team traveled across the country to face the Philadelphia Union at Subaru Park, but the match was suspended in the sixth minute due to the waterlogged field.

After an evaluation, the match was postponed to a later date; the Union's planned trip to Mexico for the CONCACAF Champions Cup made a next-day rematch infeasible.

[42][43] On April 23, the Sounders traded defender Xavier Arreaga to the New England Revolution in exchange for a 2025 international roster slot and $75,000 in general allocation money.

[46] In a midweek match at the Starfire Sports Complex, the Sounders advanced to the round of 16 in the U.S. Open Cup after defeating Louisville City FC on penalties.

[50] Back at home, the Sounders were held to a 1–1 draw against Vancouver in a match that featured the return of Pedro de la Vega who had been dealing with hamstring injuries since the first two games of the year.

[58] Rusnák then scored his own brace against Chicago Fire FC by converting penalties for a 2–1 win, putting Seattle above the playoff line in ninth place.

In July and August, MLS play halted for the Leagues Cup, an international competition with Liga MX clubs hosted in the United States and Canada.

[68] The 2024 Leagues Cup, the second edition of the expanded inter-league competition between MLS and Liga MX hosted in the United States and Canada, began on July 26.

The Sounders were drawn into group West 6 alongside Minnesota United FC and Liga MX's Club Necaxa; the competition's schedule was released on March 14, 2024.