The term federalist describes any of several political beliefs around the world, or the concept various parties; its members or supporters calling themselves "Federalists".

Federalist may also refer to:

• Federalist architecture, the name for the classicizing architecture built in the newly founded United States between c. 1780 and 1830, and particularly from 1785 to 1815
• Maryland Federalist, a replica of the 18th-century miniature ship Federalist
• The Federalist, now known as The Federalist Papers, a late-1780s collection of articles or essays promoting the ratification of the United States Constitution
• The Federalist (website), a conservative U.S. political website
• The Federalists, SFBA-based U.S. indie rock band

• Federalist Party, a former political party of the United States
• Federalist Alliance, a former political party of Italy
• Federalista Party, a former political party of the Philippines
• Federalist Unity Party, a political party of Argentina
• Democratic Party of Federalists, a political party of Bosnia and Herzegovina
• Union of Federalists and Independent Republicans, a political party of the Democratic Republic of Congo
• Union of Federalist Nationalists of Congo, a political party of the Democratic Republic of Congo
• Breton Federalist League, a former political party of Brittany
• Hungarian Federalist Party, a former political party of Slovakia
• Federalist Italian League, a former political party of Italy
• Turkic Federalist Party, a former political party of Azerbaijan
• Tuscan Federalist Alliance, or Lega Toscana, a political party of Tuscany
• The Federalist Party of the Yale Political Union, a conservative party in a debate society

• Federalist Society, U.S. conservative organisation seeking constitutional and legal reform
• Federalist Era (1789–1801), U.S. political era
• Federalism (category)
  • Federalism, a mode of government
• Anti-Federalist, a former political movement in the U.S.
• Anti-Federalist League, a cross-party organisation in the United Kingdom
• Federalist revolts, 1793 uprisings in France
• Federal (disambiguation)
• Federation (disambiguation)
• Federalism (disambiguation)
• Federal Union (disambiguation)