The incident happened on the A1 around 9.30am and involved a car and a lorry.
Emergency services attended and one of the drivers, a 29-year-old woman, was pronounced dead at the scene. The other driver was not injured.
Sergeant Mark Banner, of the Scottish Borders Road Policing Unit, said: “Enquiries into the circumstances surrounding this crash are ongoing. The road remains closed and local diversions are in place.
“We would encourage anyone who may have witnessed the crash or who may have dash-cam footage that could assist with the investigation to contact police.
“If you were in the area at the time or have any potential dash-cam footage that could assist with our investigation, I would urge that you get in touch via 101, quoting reference number 0727 of 28 December.”