While SR 551 is maintained by the Florida Department of Transportation, the southern extension is a toll road owned and operated by the Central Florida Expressway Authority (CFX).

South of the airport terminals, it curves west to meet Jeff Fuqua Boulevard, which runs from the airport south to Boggy Creek Road (CR 530) and State Road 417.

The southern extension is not assigned a state road number, but the Central Florida Expressway Authority's website displays a shield for State Road 551 Toll.

The toll currently costs $0.50 and can be paid with cash, an E-Pass or Uni transponder issued by CFX, or a SunPass transponder issued by the Florida Department of Transportation's Florida Turnpike Enterprise.

It was defined as beginning at a point on SR 15 in Section 23, T 23 S, R 30 E and running North approximately nine miles to intersection with SR 426 in Section 2, T 22 S, R 30 E.[citation needed] Since then, two changes have been made: the number was changed to SR 551 in the early 1980s, and the northernmost piece was moved from Goldenrod Road to Palmetto Avenue to avoid two curves.