Same-sex marriage legislation was introduced in successive sessions of the General Assembly from 2007 to 2013. Governor Pat Quinn signed legislation on January 31, 2011, that legalized civil unions in Illinois as of June 1, 2011. The law also allows opposite-sex couples to form civil unions and provides state recognition of substantially similar legal relationships, including same-sex marriages and civil unions, entered into in other jurisdictions.
The House of Representatives passed a bill (SB10) legalizing same-sex marriage by a 61–54 vote on November 5, 2013, and Governor Pat Quinn signed the bill into law on November 20. The law is scheduled go into effect on June 1, 2014, when same-sex couples will be able to apply for marriage licenses and then marry after the mandatory one-day waiting period.