The driver of the car, a woman aged in her 50s, was pronounced dead at the scene. The driver of the jeep, a woman aged in her 40s, was taken to Limerick University Hospital with serious injuries.
A technical examination of the scene has been completed.
Gardaí are appealing for any witnesses, particularly any road users who may have camera footage, to come forward. Anyone with information is asked to contact Gardaí in Newcastlewest on 069 20650 or the Garda Confidential Line on 1800 666 111.