This is a list of seasons played by the Portland Timbers in American soccer, from 1975, when the original club first competed in the North American Soccer League, through the most recent completed season.
This list details the club's achievements in all competitions and the top scorers for each season.
Totals include the records and statistics of all four iterations of the club.
Top goalscorer(s) includes all goals scored in League, Playoffs, U.S. Open Cup, MLS is Back Tournament, CONCACAF Champions League, FIFA Club World Cup, and other competitive continental matches.
Points and PPG have been adjusted from non-traditional to traditional scoring systems for seasons prior to 2003 to more effectively compare historical team performance across seasons.