Margaret Jamieson, 70, from Peebles, suffered fatal injuries in the accident at about 16:40 on Monday on the A703, north of Redscarhead.
Two other people - a man and a woman - were seriously injured and were taken to the Royal Infirmary of Edinburgh.
Police have urged anyone who witnessed the crash, involving a Nissan Quashqai and a VW Caddy, to contact them.
Police have named a woman killed in a crash between a car and van near Peebles in the Borders.