Implied cause of action is a term used in United States statutory and constitutional law for circumstances when a court will determine that a statute or provision that creates rights also supports a remedy that can be achieved through a lawsuit, even though no remedy is provided for in the statute.

Perhaps the best known case creating an implied cause of action is Bivens v. Six Unknown Named Agents, 403 U.S. 388 (1971). In that case, the United States Supreme Court ruled that an individual whose Fourth Amendment freedom from unreasonable search and seizures had been violated by federal agents could sue for the violation of the Amendment itself, despite the lack of any federal statute authorizing such a suit. The existence of a remedy for the violation was implied from the importance of the right violated.

In a later case, Schweiker v. Chilicky, 487 U.S. 412 (1988), the Supreme Court determined that a cause of action would not be implied for the violation of rights where the U.S. Congress had already provided a remedy for the violation of rights at issue, even if the remedy was inadequate.