The team announced the signing Tuesday. It came a day after rookie kicker Dustin Hopkins was hurt in practice, according to ESPN.com.
The Bills have not revealed Hopkins was hurt or how much time he might miss.
Carpenter has five years of NFL experience with Miami, and was selected to the Pro Bowl in 2009. He was released by the Dolphins last month and failed in tryout bids with Arizona and the New York Jets over the past two weeks.
Overall, Carpenter has converted 127 of 155 field-goal attempts. His 127 field goals are tied for fifth-most in the NFL since 2008.
The Bills open the season hosting New England on Sunday.
Source: Associated Press