The early voting law, effective in Illinois, allows voters to cast a ballot at an early voting center starting Monday, March 5th through Monday, March 19th in the permanent locations. As all ballot styles for McHenry County are available at Early Voting Centers, voters may choose to vote at the site most convenient for them. See PDF for Dates and Times for Early Voting. Vote by Mail requests will be accepted now through March 15, 2018. Ballots will be mailed starting Feb. 8, 2018 and must be returned postmarked no later than midnight of Election Day, March 20, 2018. Any voter who requests a “ Vote by Mail” ballot may go t o the polls on Election Day and surrender the ballot originally requested.