Biden, 77, a longtime senator who served for eight years under Democratic President Barack Obama, would join a crowded field of nearly 20 other candidates seeking to defeat Republican President Donald Trump.
The Atlantic previously reported that Biden would announce his candidacy on Wednesday.
Biden’s announcement would end months of speculation over whether he would seek to challenge Trump, who followed Obama in the White House following his 2016 victory over Democrat Hillary Clinton.
Next Monday, Biden will meet with union workers in Pittsburgh, a pivotal election region in Pennsylvania that backed Trump in 2016, an NBC news reporter said on MSNBC, citing unnamed sources involved in the planning. CNN also reported the planned event.
Trips will follow to all four early voting states – Iowa, New Hampshire, South Carolina and Nevada – in coming weeks, NBC reported, adding that all of the details were still being finalized.
Representatives for Biden did not have any immediate comment on the reported plans.
Biden unsuccessfully ran for the presidency twice before and more recently has faced questions about his interactions with women who said he made them feel uncomfortable. Biden has said he believed he never acted inappropriately but would be more mindful about his behavior.
(Reporting by Susan Heavey; Editing by Tim Ahmann and Grant McCool)