By the end of 1953, estimates and contracts had been negotiated. Total cost estimate at that time was $95 million dollars with estimated completion by November 1, 1956. Tolls collected were to pay for the bridge in 20 years.[9]

The Mackinac Bridge is currently a toll bridge on Interstate 75 (I-75). Prior to the coming of I-75, the bridge carried US Highway 27 (US 27). It is one of only three segments of I-75 that are tolled, the others being the American half of the International Bridge near Sault Ste. Marie, Michigan, and Alligator Alley in Florida. The current toll is $4.00 for automobiles and $5.00 per axle for trucks.[2] The Mackinac Bridge Authority recently raised the toll to fund a $300 million renovation program, which would include completely replacing the bridge deck.[12]