The "Evidence-Based Grantmaking Act" amends Title 5 of the U.S. Code, requiring designated federal departments and agencies, referred to as covered agencies , to implement evidence-based practices for covered grants that provide services to the public or specific communities. Agencies must include a clearly defined purpose and intended outcomes in all grant opportunities, prioritizing applicants who demonstrate the use of evidence-based practices and responsiveness to community needs. Grant recipients will be required to use evidence-based practices when providing services funded by these grants. The bill mandates that agencies, through their Evaluation Officers, conduct periodic, evidence-based evaluations during the grant term to assess effectiveness, making results public and using them to inform future grantmaking decisions. To ensure consistent application, the Office of Management and Budget (OMB) is tasked with issuing guidance on how to define and apply "evidence-based" within one year. Following this, each covered agency must define "evidence-based" for its grants, establish a framework for identifying evidence-based applicants with public comment, and begin implementing this framework five years after the Act's enactment. Agencies are required to submit annual reports to Congress on their activities, while OMB will provide annual reports to Congress on the overall progress of implementation, assessing agency alignment and offering recommendations for streamlining the application process.