[295] On July 3, Jefferson was overcome by fever and declined an invitation to Washington to attend an anniversary celebration of the Declaration.[296]

During the last hours of his life, he was accompanied by family members and friends. Jefferson died on July 4 at 12:50 p.m. at age 83, the same day as the 50th anniversary of the Declaration of Independence. His last recorded words were "No, doctor, nothing more," refusing laudanum from his physician, but his final significant words are often cited as "Is it the Fourth?"or "This is the Fourth."[297] When John Adams died later that same day, his last words included an acknowledgment of his longtime friend and rival: "Thomas Jefferson survives," though Adams was unaware that Jefferson had died several hours before.[298][299][300][301] The sitting president was Adams's son, John Quincy Adams, and he called the coincidence of their deaths on the nation's anniversary "visible and palpable remarks of Divine Favor."[302]
Shortly after Jefferson had died, attendants found a gold locket on a chain around his neck, where it had rested for more than 40 years, containing a small faded blue ribbon that tied a lock of his wife Martha's brown hair.