Localizing Authority of Management Plans Act of 2018 or the LAMP Act of 2018 This bill amends the Endangered Species Act of 1973 (ESA) to revise requirements governing cooperative management agreements to manage areas established for the conservation of endangered or threatened species. Under current law, the agreements are between states and the Department of the Interior or the Department of Commerce, as appropriate. This bill allows the appropriate department to enter into: (1) agreements with local governments, Indian tribes, or nonfederal persons; and (2) agreements to manage areas established for the conservation of species that are candidates for listing. The bill exempts the actions of preparing, approving, and entering into an agreement from environmental review requirements under the National Environmental Policy Act of 1969. The departments may: (1) delegate authority under the ESA to states that establish and maintain an adequate program for the conservation of endangered or threatened species that reside in the state, and (2) provide financial assistance to a state that has entered into an agreement with the department or to a state with delegated authority.