First, the various states all have their own deadlines to certify the election results, making them official. In several key states, those deadlines are fast approaching — for instance, Georgia’s is this Friday. Trump has been trying to slow down or block these certifications, but he’s had little success so far.
Federal law sets the deadline for all states to certify their presidential election results and appoint electors at December 8. But the various states have set earlier deadlines for themselves, and the Washington Post’s Elise Viebeck and Daniela Santamariña put together an excellent rundown of all the important dates to watch.
Second, the Electoral College will meet and cast the votes that will formally make Joe Biden the president-elect on December 14. Unless Trump can somehow get his own electors appointed in states Biden won, that would make it truly official that he’s lost.
There’s a lot more detail in the full article