The Research Experiences for Undergraduates (REU) Sites and Supplements program, administered by the National Science Foundation (NSF), provides funding to support active undergraduate student participation in research. This opportunity includes two distinct mechanisms: REU Sites and REU Supplements. REU Sites involve independent proposals submitted by institutions to host multiple undergraduate researchers around a coherent research theme. REU Supplements allow principal investigators with existing NSF grants to request additional funding to include undergraduates in their ongoing projects.

The program is intended to provide meaningful, high-quality research experiences that engage students in scientific inquiry under the guidance of mentors. It is particularly focused on attracting a diverse range of participants and expanding opportunities for students who might not otherwise have access to such experiences, including those from academic institutions with limited STEM research opportunities. Students are expected to be involved in research activities that enhance their academic development and career trajectory.

Eligible applicants for this funding include institutions of higher education and other research organizations identified in the NSF Proposal & Award Policies & Procedures Guide (PAPPG). REU Sites must ensure that a significant portion of their student participants come from outside the host institution, with at least half from institutions where STEM research opportunities are limited. Undergraduate participants must be U.S. citizens, nationals, or permanent residents. Additional partnerships are available with federal entities like the Department of Defense and Department of Energy, potentially offering co-funding for aligned research.

Applications for REU Site proposals must be submitted through Research.gov or Grants.gov, with submission guidelines conforming to the PAPPG. Proposals require a detailed project summary, description of student research activities, plans for student recruitment and mentoring, and a budget focused on student support. No letters of intent or preliminary proposals are required. The budget should prioritize student stipends, housing, and travel, with indirect costs prohibited on participant support expenses. The average funding ranges between $100,000 to $155,000 per year.

Evaluation of proposals will consider both intellectual merit and broader impacts, with emphasis on the quality and value of the research experience, mentoring environment, diversity of student recruitment, and effectiveness of program management and evaluation. Reporting requirements include annual and final reports detailing student outcomes and demographics, and awardees must maintain a dedicated website for student recruitment.