Trump will be more than 2,300 miles away, watching the debate between Republican Mike Pence and Democrat Tim Kaine from the comfort of the Trump International Hotel in Las Vegas.
Clinton will most likely watch from her home in Chappaqua, New York, an aide told ABC News.
Both Trump and Clinton have campaign events scheduled today – he in Arizona and she in Pennsylvania — so it’s a matter of Clinton’s making it home from that event.
The debate starts at 9 p.m. ET and will run for 90 minutes.
ABC News’ John Santucci and Liz Kreutz contributed to this report.
Watch FULL LIVE COVERAGE of the second presidential debate, co-moderated by ABC News’ Martha Raddatz, at 9 p.m. ET on Sunday, Oct. 9. Coverage and analysis of the debate will begin on ABCNews.com/Live at 7 p.m. ET.