Police have appealed for information following the assault on the Black Path yesterday (Monday, February 18) around 10.50am.
The woman was walking alone at the time.
The suspect, also a woman, is believed to have been aged between 20 and 25. She is described as being around five feet five inches tall, of average build, and with dark shoulder length hair. She was wearing a black jacket and denim jeans.
Anyone with information should contact Galashiels police station on 01896 752222.