You may register to vote at any City of Madison library branch until 5 p.m. today. From July 24 through August 8, you can only register in the City Clerk's Office with proof of address. You also have the option of registering at the polls on Election Day with proof of address.
Registrations sent by mail must be postmarked by today. Start the registration process online at https://MyVote.wi.gov. Print, sign, and mail the registration form to: City Clerk, 210 Martin Luther King Jr Blvd #103, Madison, WI 53703. First-time Wisconsin voters are required to include proof of address (copy of one of the following documents showing the voter's name and current address: utility bill, WI driver license/ID, government document, paycheck, or bank/credit union statment).