Ohio Rev. Code Ann. § 709.10

The annexation shall become effective thirty days after the passage of the resolution or ordinance by the legislative authority of the municipal corporation accepting annexation, provided that if the resolution or ordinance is subjected to a referendum, the annexation, if approved by the electors, shall become effective thirty days after such approval. The territory annexed is a part of the municipal corporation, and the inhabitants residing therein shall have all the rights and privileges, and shall be subject to the powers, of the municipal corporation as are the inhabitants within the original limits of such municipal corporation.