| Illinois Open Championship | |
| Location: | varies – Flossmoor, Illinois in 2023 |
| Course: | varies – Flossmoor CC in 2023 |
| Establishment: | 1950 |
| Par: | 72 (in 2023) |
| Yardage: | 6975yd (in 2023) |
| Org: | Illinois PGA |
| Format: | 54-hole stroke play |
| Month Played: | August |
| Current Champion: | Vince India |
The Illinois Open Championship is a golf tournament that is administered by the Illinois PGA (Professional Golfers' Association). The state championship of golf is a 54-hole championship over three days to determine the finest player in the state of Illinois. The tournament is open to professionals and amateurs with a handicap of 10 or less who reside within the state of Illinois.
In 2015, for the first time in the history of the Illinois Open, the Illinois PGA changed the format of the event having it contested at two facilities for the first and second rounds.
The final championship field size after qualifying events increased from 156 to 258 players. The number of competitors making the cut also increased to the top 70 and ties from the top 50 and ties. Qualifying events conducted throughout the month of June finalize the championship field to the top 258 players.
| Year | Champion | Venue | Location | Score | Low amateur | |
|---|---|---|---|---|---|---|
| 2023 | 208 (−8) PO | Quinn Clifford | ||||
| 2022 | 210 (−6) | Marcus Smith | ||||
| 2021 | 199 (−17) | Mac McClear | ||||
| 2020 | 208 (−8) | Jordan Less | ||||
| 2019 | David Cooke | 203 (−13) | Bryan Baumgarten, Jordan Less | |||
| 2018 | 202 (−14) | David Perkins | ||||
| 2017 | Patrick Flavin (a) | 201 (−13) | Patrick Flavin | |||
| 2016 | 197 (−17) | Nick Hardy | ||||
| 2015 | David Cooke (a) | 199 (−16) | David Cooke | |||
| 2014 | Brad Hopfinger | 210 (−6) | Brian Payne, Dan Stringfellow | |||
| 2013 | Joe Kinney | 211 (−5) PO | Dustin Korte | |||
| 2012 | Max Scodro | 206 (−10) PO | Brett Tomfohrde | |||
| 2011 | Philip Arouca | 202 (−11) | Ravi Patel | |||
| 2010 | Eric Meierdierks | 201 (−6)*** | Luke Guthrie | |||
| 2009 | Brad Benjamin (a) | 208 (−5) PO | Brad Benjamin | |||
| 2008 | Joe Emerich (a) | 208 (−5) | Joe Emerich | |||
| 2007 | 136 (−6)** | Joe Cermak | ||||
| 2006 | 205 (−11) | Carlos Sainz | ||||
| 2005 | 208 (−8) | Andy Pope | ||||
| 2004 | 210 (−6) PO | Kevin Tassistro | ||||
| 2003 | 203 (−13) | Andrew Price, John Wright | ||||
| 2002 | Brian Payne | 207 (−6) | Scott Harrington | |||
| 2001 | Roy Biancalana | 212 (−1) PO | Joe Affrunti | |||
| 2000 | Curtis Malm (a) | 209 (−4) | Curtis Malm | |||
| 1999 | Adam Turner (a) | 207 (−9) | Adam Turner | |||
| 1998 | Todd Tremaglio | 209 (−7) PO | D. A. Points | |||
| 1997 | Marty Schiene | 205 (−11) | Bill Hoffer | |||
| 1996 | 204 (−12) | Michael Cushin, Bill Hoffer | ||||
| 1995 | 211 (−2) | Chip Travis | ||||
| 1994 | 207 (−6) | Bill Hoffer | ||||
| 1993 | Dino Lucchesi | 208 (−5) | Bill Hoffer, Lee Kolquist | |||
| 1992 | Marty Schiene | 205 (−8) PO | Lee Kolquist | |||
| 1991 | Marty Schiene | 211 (−2) | Lee Kolquist | |||
| 1990 | Gary Pinns | 208 (−8) | Rich Dukelow | |||
| 1989 | Bob Ackerman | 207 (−9) | Joel Hirsch | |||
| 1988 | Gary Pinns | 213 (E) | Jack Fritsch, Robert Sullivan | |||
| 1987 | Roy Biancalana | 206 (−10) | George Glickley | |||
| 1986 | Gary Pinns | 210 (−3) | Gary March | |||
| 1985 | Gary Pinns | 209 (−7) | Brad Barker | |||
| 1984 | 207 (−9) | Bill Hoffer | ||||
| 1983 | Bill Hoffer (a) | 212 (−4) PO | Bill Hoffer | |||
| 1982 | 212 (−4) PO | Andy Shuman | ||||
| 1981 | Rick Ten Broeck (a) | 213 (−3) | Rick Ten Broeck | |||
| 1980 | David Ogrin (a) | 210 (−3) | David Ogrin | |||
| 1979 | Jim Urban | 208 (−5) | George Glickley | |||
| 1978 | Gary Pinns (a) | 212 (−4) | Gary Pinns | |||
| 1977 | Gary Hallberg (a) | 208 (−8) | Gary Hallberg | |||
| 1976 | Dennis Sullivan | 217 (+4) | John Baldwin | |||
| 1975 | Bill Erfurth | 210 (−3) | Bruce Johnson | |||
| 1974 | Emil Esposito | 212 (−4) | Dennis Sullivan | |||
| 1973 | Rick Ten Broeck | 209 (−4) PO | Gary Ostrega | |||
| 1972 | John Gostele | 212 (−1) | Tom Benjamin | |||
| 1971 | 212 (+2) | Joel Hirsch | ||||
| 1970 | Al Bailey | 211 (−5) | Joel Hirsch | |||
| 1969 | 217 (+1) PO | Bob Zender | ||||
| 1968 | Chick Evans (a) | 214 (+4) | Gene Howard | |||
| 1967 | Bill Ogden | 213 (E) | Jack Charron | |||
| 1966 | Emil Esposito | 220 (+7) PO | Earl Liff | |||
| 1965 | 212 (−4) | Tull Monsees | ||||
| 1964 | Medinah Country Club, Course No. 3 | 224 (+8) PO | Frederic Franz | |||
| 1963 | Jack Bell | 209 (−7) | Gene Howard | |||
| 1962 | John Paul Jones | 215 (−1) | Ed Carroll | |||
| 1961 | Chuck Malchaski | Medinah Country Club, Course No. 3 | 221 (+5) | Bernard Magnussen | ||
| 1960 | Bob Bruno | Olympia Fields Country Club, North Course | 215 (+2) | Martin Stanovich | ||
| 1959 | Jack Bell | 217 (+1) | Jim McCarthy, Dean Refram | |||
| 1958 | 215 (+2) | Martin Stanovich | ||||
| 1957 | Jock Hutchison Jr. | 213 (E) | Harold Foreman Jr. | |||
| 1956 | Bob Harris | 215 (−1) | John Wagner | |||
| 1955 | Bob Harris | 209 (−7) | John Wagner | |||
| 1954 | George Bolesta | Olympia Fields Country Club, North Course | 219 (+4) | John Dobro | ||
| 1953 | 138 (−2) * | Harold Foreman Jr. | ||||
| 1952 | Bill Ogden | 142 (E) PO * | George Victor | |||
| 1951 | Jackson Bradley | 140 (−4) * | John Wagner | |||
| 1950 | 139 (−5) * | Art Hoff |
The modern incarnation of the Illinois Open dates back to 1950. However, records show Jock Hutchison winning the 1920 Illinois Open, Leo Diegel winning in 1924 and "Lighthorse" Harry Cooper winning in 1933, 1934 and 1935.