From New York City (Queens), she is the daughter of O. Urcille Ifill, Sr. a Methodist preacher and Eleanor IFill. She has a sister and brother, Maria Ifill Philip and Roberto. In 1977, she graduated from Simmons College in Boston, Massachusetts where she majored in communications, and through an internship got her first hands-on experience as a journalist. Ifill has also received 15 honorary degrees.
She earlier worked for the Boston Herald, the Baltimore Sun, The Washington Post, The New York Times, and NBC. Ifill became moderator of the PBS program Washington Week in Review in October 1999 and is also senior correspondent for the NewsHour with Jim Lehrer. On October 5, 2004, she moderated the vice presidential debate between Dick Cheney and John Edwards. Ifill serves on the board of the Harvard Institute of Politics, the Committee to Protect Journalists, the Museum of Television and Radio and the University of Maryland's Philip Merrill College of Journalism.