Spc. Richard Ashley accepted a plea deal with prosecutors, but the terms of the deal were not immediately known. The plea will be finalized in court next week.
Ashley is charged with pandering, wrongfully engaging in sexual acts with another and sodomy.
If he were to stand trial, the maximum sentence he could have received would have been one year of jail time and a bad conduct discharge.
Two other soldiers, Pfc. Wesley Mitten and Pvt. Kagen Mullen, are still awaiting trial in the case.
Four other soldiers agreed to leave the U.S. Army without courts-martial.