Two hundred eighty-one sporadic Neisseria meningitidis serogroup B isolates, collected through active laboratory-based surveillance, were selected to be analyzed by PorA variable region (VR) typing to determine the prevalence of PorA types in the United States. A substantial number of distinct VR types were identified, 31 in VR1 and 41 in VR2. A total of 73 different PorA types were found, and 76.7% of these types comprise nonprototype sequences in VR1, VR2, or both. The most prevalent PorA types were P1.7, 16–20 (previously P1.7, 16i), P1.22, 14, P1.22-1, 14 (previously P1.22a, 14), P1.7, 16, P1.7-1, 1 (previously P1.7d,1), P1.19, 15, and P1.17, 16-3 (previously P1.B, 16d). No correlation was observed between the PorA types and geographic origin of the isolates. These data may aid in the design of an efficacious outer membrane protein—based vaccine by identifying the most appropriate PorA types for vaccine formulation. Studies are needed to fully evaluate the extent of cross-protection in humans among the variants and prototypes in each PorA VR family.