State and Local Cybersecurity Improvement Act This bill establishes a grant program administered by the Federal Emergency Management Agency (FEMA) for state, territorial, and tribal governments to address cybersecurity risks and threats to information systems. A grant applicant must submit a cybersecurity plan that assesses current efforts to address cybersecurity concerns and outlines grant-funded activities. FEMA may award grant funding to support the development of a plan. A grant recipient must make available at least 80% of funds to local governments with a particular focus on rural areas. The bill requires various reports concerning the grant program, including an assessment of cybersecurity needs of tribal governments. The Government Accountability Office must also study the program.