Harris, of Asian descent, has had a career of firsts and will add another after assuming the office of vice president.
United States Vice President-elect Kamala Harris will resign her Senate seat on Monday, her aides have confirmed, just days before she and President-elect Joe Biden will be inaugurated on January 20.
Harris will leave the Senate shortly after Democrats narrowly secured a majority there, winning two election runoffs in Georgia this month.
With Democrats holding 50 of the chamber’s 100 seats, Harris will cast tie-breaking votes.
She will not give a farewell speech on the Senate floor as it is not set to reconvene until Tuesday.
Harris’s seat will be filled by Democrat Alex Padilla, California’s Secretary of State, who was selected by Governor Gavin Newsom. Padilla will become the first Latino senator to represent the state, where about 40 percent of residents are Latino.
Harris, meanwhile, will become the first woman to serve as vice president, as well as the first Black person and person of South Asian descent to fill the role.
She had previously been only the second Black woman to hold a Senate seat.
Harris has chosen US Supreme Court Justice Sonia Sotomayor to swear her in as vice president on Wednesday. Sotomayor swore in Biden as vice president in 2013.
She will use two bibles for the swearing-in ceremony, including one owned by Thurgood Marshall, the first Black US Supreme Court justice.
Marshall and Harris both attended Howard University, a renowned historically Black university. The vice president-elect has called Marshall one of her “greatest heroes”.
Wednesday’s pared-down inauguration comes just over two weeks after President Donald Trump’s supporters, egged on by the president, stormed the US Capitol as Congress met to certify Biden’s election victory.
Authorities have warned of further violence surrounding the inauguration and put increased security in place in Washington, DC, and various US state capitals.
Prior to the Capitol riot, Biden had said the inauguration would be a toned-down affair in light of the COVID-19 pandemic.