The justices' decision upholds the 4th U.S. Circuit Court of Appeals' May ruling in the case, which dismissed as invalid Liberty's argument that the law violated the Constitution in requiring employers to offer health insurance.
The high court previously upheld the constitutionality of the health care law's insurance mandate in a landmark 2012 decision.
The Supreme Court announced Tuesday that it would hear two cases challenging the health care law's birth control mandate on religious grounds, Hobby Lobby Stores, Inc. v. Sebelius and Conestoga Wood Specialties Corp. v. Sebelius. Those cases are slated to be heard next spring.