Tribal Recognition Act of 2018 This bill replaces the process for federal recognition of Indian tribes. Indian groups may only be recognized as an Indian tribe by Congress. Groups that are not federally recognized may submit a petition for federal recognition to the Bureau of Indian Affairs (BIA) within five years after enactment of this bill. Groups may not be factions of recognized Indian tribes and may not have been denied federal recognition. The BIA must publish guidelines for the preparation of petitions and provide petitioners with suggestions and advice. The bill specifies criteria for a group to be considered an Indian tribe, including that the group has been identified as an Indian entity on a substantially continuous basis since 1900, comprises a distinct community, and consists of individuals who descend from a historical Indian tribe. Previous federal recognition is acceptable evidence of the tribal character of a group to the date of the last such recognition. The bill reaffirms as trust land all land taken into trust by the United States under or pursuant to the Act of June 18, 1934 before February 24, 2009, for the benefit of an Indian tribe that was federally recognized on the date that the land was taken into trust.