The 1973 Rainier International Tennis Classic, also known as the Seattle International, was a men's tennis tournament staged at the Seattle Center Arena in Seattle, Washington in the United States that was part of the Grand Prix circuit and categorized as a Group C event.

The tournament was played on indoor carpet courts and was held from September 10 until September 16, 1973.

It was the second and last edition of the tournament and second-seeded Tom Okker won the singles title and earned $7,500 first-prize money as well as 20 ranking points.

[3][4] Tom Okker defeated John Alexander 7–5, 6–4 Tom Gorman / Tom Okker defeated Bob Carmichael / Frew McMillan 2–6, 6–4, 7–6