"Hey twitterbugs! I will not be doing DWTS this season. But be sure to tune in! <3," wrote Schwimmer, 21.
See cute pics of stars rehearsing for DWTS
About 30 minutes later, she added, "I'm off to bed! I'm sad I will not be on this season of #dwts too yall! Biglove<3."
See what DWTS contestants looked like before they joined the show!
Schwimmer joined DWTS in 2008 after coming in fourth place on So You Think You Can Dance. Her star partners have included Lance Bass and Iron Chef host Mark Dacascos.
Harris announced last month that she will no longer be the show's co-host alongside Tom Bergeron. She told Us she plans to take on "expanded responsibilities on The Insider."
Check out a slideshow of Samantha's DWTS style!
The 10th season kicks off March 22.