DYFED-Powys Police were called to a single vehicle RTC on Llandeilo Road, Cross Hands, at around 4:30pm today (Thursday, June 7).
The vehicle had left the carriageway and collided with a lamp post before coming to rest against the front of a house.
Despite the best efforts of members of the public, police, fire and air ambulance crews, the driver of the vehicle was sadly pronounced dead at the scene.
No other vehicles were believed to be involved and no one else was hurt.
The house did not suffer any structural damage and no one was home at the time of the collision.
Anyone who witnessed the incident is asked to contact PC 814 Brookes of Carmarthenshire Roads Policing Unit via 101.