The Court said Thomas had been admitted to Sibley Memorial Hospital in Washington, D.C., last Friday with an infection. He had been suffering "flu-like symptoms."
In a Sunday press release, the Court noted Thomas had was responding well to treatments that his symptoms were "abating" thanks to intravenous antibiotics.
News of Thomas' release comes a day after reports emerged that his wife, Virginia, urged then-White House Chief of Staff Mark Meadows to pursue actions that would overturn the results of the 2020 election.
His release also comes as the Senate considers the confirmation of Ketanji Brown Jackson to the high court after four days of hearings.