The price includes a $925 destination charge and reflects a price cut of $2,570 compared to the current base LaCrosse.
"This is part of a larger strategy for Buick and GMC to attract new buyers who may be cross-shopping vehicles in critical segments," wrote GM spokeswoman Kelly Cusinato in response to a query from Edmunds.
Cusinato noted that there are some "minor content changes" on the new base LaCrosse, including the substitution of 17-inch wheels for 18-inch wheels on the V6 model.
The new base LaCrosse is not at dealerships yet. The GM digital team is working to update the vehicle configurator on the Buick consumer Web site.
Automotive News reports that a major redesign of the LaCrosse is due in about a year.
Edmunds says: With this strategy, the 2015 Buick LaCrosse undercuts the Kia Cadenza, Lexus ES 350 and Toyota Avalon, something that car shoppers on a budget should appreciate.