| Team | League | League | GP | W | L | T | GF | GA | Pts | Finish | Att |
| Portland Timbers | 1975 NASL Pacific Division | 22 | 16 | 16 | 6 | | 43 | 27 | 138 | 1st | 14503 |
| 1st round: Portland defeated Seattle 2-1 |
| Semifinals: Portland defeated St. Louis 2-1. |
| Soccer Bowl 75 at San Jose: Tampa Bay defeated Portland 2-0 |
| Portland Timbers | 1976 NASL Pacific Conf-Western Division | 24 | 16 | 8 | 16 | | 23 | 41 | 71 | 3rd | 20515 |
| Portland Timbers | 1977 NASL Pacific Conf-Western Division | 26 | 16 | 10 | 16 | | 39 | 42 | 98 | 4th | 13216 |
| Portland Timbers | 1978 NASL National Conf-Western Division | 30 | 16 | 20 | 10 | | 50 | 36 | 167 | 2nd | 11803 |
| 1st round: Portland defeated Washington 2-1 |
| 2nd round: Portland defeated Vancouver 1-0, 2-1 |
| Semifinals: Cosmos defeated Portland 1-0, 5-0 |
| Portland Timbers | 1979 NASL National Conf-Western Division | 30 | 16 | 11 | 19 | | 50 | 75 | 122 | 4th | 11172 |
| Portland Timbers | 1980 NASL National Conf-Western Division | 32 | 16 | 15 | 17 | | 50 | 53 | 133 | 4th | 10210 |
| Portland Timbers | 1981 NASL Northwest Division | 32 | 16 | 17 | 15 | | 52 | 49 | 141 | 3rd | 10516 |
| 1st round: San Diego defeated Portland 1-2,5-1,2-0 |
| Portland Timbers | 1982 NASL Western Division | 32 | 16 | 14 | 18 | | 49 | 44 | 122 | 4th | 8786 |
| F.C. Portland | 1985 WSA | 7 | 16 | 1 | 4 | 2 | 8 | 16 | 5 | 4th | |
| F.C. Portland | 1986 WSA | 14 | 16 | 6 | 6 | 2 | 20 | 19 | 20 | 2nd | |
| F.C. Portland | 1987 WSA | 10 | 16 | 5 | 5 | | 9 | 16 | 24 | 4th | |
| F.C. Portland | 1988 WSA | 12 | 16 | 1 | 11 | | 16 | 32 | 22 | 6th | |
| Portland Timbers | 1989 WSA North Division | 16 | 16 | 11 | 5 | | 32 | 25 | 92 | 2nd | |
| Semifinals: San Diego defeated Portland 2-1 |
| Portland Timbers | 1990 APSL West Conference-North Division | 20 | 16 | 10 | 10 | | 42 | 36 | 99 | 4th | |
| Portland Firebirds | 1995 USISL Northwest Division | 20 | 16 | 9 | 11 | | 36 | 30 | 91 | 4th | |
| Portland Timbers | 2001 A-League Western Conference | 26 | 16 | 13 | 10 | 3 | 41 | 38 | 62 | 3rd | 6124 |
| 1st Round: Portland defeated Charlotte 2-0, 3-2 |
| Quarterfinals: Hershey defeated Portland 2-0, 1-0 |
| Portland Timbers | 2002 A-League Western Conf-Pacific Division | 28 | 16 | 13 | 12 | 3 | 47 | 39 | 63 | 2nd | 6261 |
| 1st Round: Vancouver defeated Portland 1-0, 1-0 |
| Portland Timbers | 2003 A-League Western Conf-Pacific Division | 28 | 16 | 15 | 11 | 2 | 39 | 33 | 47 | 3rd | 5871 |
| Portland Timbers | 2004 A-League Western Conference | 28 | 16 | 18 | 7 | 3 | 58 | 30 | 57 | 1st | 5281 |
| 2004 A-League Regular Season Champion |
| 1st Round: Seattle defeated Portland, 1-2, 1-0 (3-2 in series OT) |
| Portland Timbers | 2005 United Soccer Leagues First Division | 28 | 16 | 10 | 9 | 9 | 40 | 42 | 39 | 5th | 5553 |
| 1st Round: Seattle defeated Portland 1-0, 2-0 |
| Portland Timbers | 2006 United Soccer Leagues First Division | 28 | 16 | 7 | 15 | 6 | 25 | 39 | 27 | T-11th | 5575 |
| Portland Timbers | 2007 United Soccer Leagues First Division | 28 | 16 | 14 | 5 | 9 | 32 | 18 | 51 | 2nd | 6828 |
| 1st Round: Portland defeated Vancouver 0-1, 3-0 |
| Semifinals: Atlanta defeated Portland 1-1, 0-0 (3-1 in shootout) |
| Portland Timbers | 2008 United Soccer Leagues First Division | 30 | 16 | 7 | 10 | 3 | 26 | 33 | 31 | 11th | 8247 |