| Year | Venue | # of attendees | |
|---|---|---|---|
| 1976 | Amsterdam | 650 | |
| 1978 | |||
| 1981 | Montreal | 2806 | |
| 1984 | |||
| 1986 | Tokyo | 1000 | |
| 1987 | |||
| 1990 | |||
| 1991 | Karlshure | 2000 | |
| 1992 | |||
| 1993 | |||
| 1994 | |||
| 1995 | |||
| 1996 | San Deigo | 2000 | |
| 1997 | |||
| 1998 | |||
| 1999 | |||
| 2000 | |||
| 2001 | Melbourne | 1700 | |
| 2002 | |||
| 2003 | † co-held with | ||
| 2004 | EFCE | ||
| 2005 | Glasgow | 1946 | |
| 2006 | |||
| 2007 | |||
| 2008 | IACChE | ||
| 2009 | Montreal | 2587 | |
| 2010 | |||
| 2012 | APCChE | ||
| 2013 | Seoul | 1670 | |
| 2014 | |||
| 2015 | |||
| 2016 | EFCE | ||
| 2017 | Barcelona | >3000 | |
| 2018 | |||
| 2019 | |||
| 2022 | IACChE | ||
| 2023 | Bueno Aires | ||
| 2024 | APCChE | ||
| 2025 | Beijing | ~5000 | |
| 2027 | EFCE | ||
| 2029 | Prague | ||
| 2031 |
† After WCEC was formed in 2001, it was decided that WCCE is co-held with the (con)federation congress in odd years.