The contracting states of the EPC are:
| CODE | COUNTRY | DATE | EXTENSION |
| AL | Albania | 1 May 2010 | 1 February 1996 – 30 April 2010 |
| AT | Austria | 1 May 1979 | |
| BA | Bosnia and Herzegovina | 1 December 2004 -… | |
| BE | Belgium | 7 October 1977 | |
| BG | Bulgaria | 1 July 2002 | |
| CH | Switzerland | 7 October 1977 | |
| CY | Cyprus | 1 April 1998 | |
| CZ | Czech Republic | 1 July 2002 | |
| DE | Germany | 7 October 1977 | |
| DK | Denmark | 1 January 1990 | |
| EE | Estonia | 1 July 2002 | |
| ES | Spain | 1 October 1986 | |
| FI | Finland | 1 March 1996 | |
| FR | France | 7 October 1977 | |
| GB | United Kingdom | 7 October 1977 | |
| GR | Greece | 1 October 1986 | |
| HU | Hungary | 1 January 2003 | |
| HR | Croatia | 1 January 2008 | 1 April 2004 – 31 December 2007 |
| IE | Ireland | 1 August 1992 | |
| IS | Iceland | 1 November 2004 | |
| IT | Italy | 1 December 1978 | |
| LI | Liechtenstein | 1 April 1980 | |
| LT | Lithuania | 1 December 2004 | 5 July 1994 – 30 November 2004 |
| LU | Luxembourg | 7 October 1977 | |
| LV | Latvia | 1 July 2005 | 1 May 1995 – 30 June 2005 |
| MC | Monaco | 1 December 1991 | |
| ME | Montenegro | 1 March 2010 -… | |
| MK | Former Yugoslav Republic of Macedonia | 1 January 2009 | 1 November 1997 – 31 December 2008 |
| MT | Malta | 1 March 2007 | |
| NL | Netherlands | 7 October 1977 | |
| NO | Norway | 1 January 2008 | |
| PL | Poland | 1 March 2004 | |
| PT | Portugal | 1 January 1992 | |
| RO | Romania | 1 March 2003 | 15 October 1996 – 28 February 2003 |
| RS | Serbia | 1 October 2010 | 1 November 2004 – 30 September 2010 |
| SE | Sweden | 1 May 1978 | |
| SI | Slovenia | 1 December 2002 | 1 March 1994 – 30 November 2002 |
| SK | Slovakia | 1 July 2002 | |
| SM | San Marino | 1 July 2009 | |
| TR | Turkey | 1 November 2000 |
The states allowing validation are: Cambodia, Morocco, the Republic of Moldova, and Tunisia.