Czech European Union membership referendum, 2003

A referendum on joining the European Union was held in the Czech Republic on 13 and 14 June 2003. The proposal was supported by 77.3% of voters, with a turnout of 55.2%. The Czech Republic joined the EU on 1 May 2004.

Opinion polls in the run-up to the referendum showed support for joining from 63% to over 70%, with the highest support among younger, wealthier and better educated people.

...
Wikipedia