The duo, who had previously been scheduled to perform through July 28, will remain with the show through Aug. 11.
Forever Tango began performances July 9 at the Water Kerr Theatre.
Smirnoff and Chmerkovskiy join five-time Grammy Award winner Gilberto Santa Rosa, who will perform through July 28. The production continues through Sept. 15.
Smirnoff and Chmerkovskiy, who met in a Broadway production of Burn the Floor, became engaged New Year's Day 2009 and broke up October of the same year.
Chmerkovskiy's credits include Le Rêve – The Dream at Wynn Las Vegas, Broadway's Burn the Floor and various television projects. He has launched one of nation's leading Latin and ballroom dance studios, Dance with Me, which has four locations across New York, New Jersey and Connecticut.
"It is such an honor to have been given this opportunity to star on Broadway again," Smirnoff said in a statement. "Forever Tango is an incredible production and the Tango is an intense, sensuous dance of passion. Asking Maks to join me was in and of itself intense, so I figured by opening night, it would be explosive!"
Forever Tango features 16 tango dancers, one vocalist and an 11-piece orchestra. Forever Tango originally opened on Broadway in 1997, receiving numerous Drama Desk and Tony Award nominations. It returned to Broadway for a four-month engagement in 2004.
More information can be found by visiting forevertangobroadway.com.