Just what that means on the roads and in the bars is still up in the air.
Police say the limit will likely mean more arrests, but they aren't sure how many because no one's tracked people who tested under Wisconsin's old limit of .10 before.
Prosecutors are split on whether the new limit will mean more trials. Waukesha County District Attorney Paul Bucher says most drunken drivers are at .10 or more.
Debbie Skrzypchak is the manager of Loppnow's Bar in Wausau. She says the new limit will make it tougher for bartenders to know when to stop serving people. She says people should be responsible for themselves.
The National Highway Traffic Safety Administration estimates the new limit will save about two dozen lives annually.