The Federal Supplement is a case law reporter published by West Publishing in the United States that includes select opinions of the United States district courts since 1932, and is part of the National Reporter System. Although the Federal Supplement is an unofficial reporter and West is a private company that does not have a legal monopoly over the court opinions it publishes, it has so dominated the industry in the U.S. that legal professionals uniformly cite the Federal Supplement for included decisions. Approximately 40 new volumes are published per year.

Law reports or reporters are series of books that contain judicial opinions from a selection of case law decided by courts. When a particular judicial opinion is referenced, the law report series in which the opinion is printed will determine the case citation format.