The two-car crash happened at around 2.30pm near Winterbourne Stoke.
An air ambulance was in attendance and the three people were taken to Salisbury District Hospital.
A spokesperson for the South Western Ambulance Service NHS Foundation Trust (SWASFT) said: “We were called at 14.36hrs to an incident in the Winterbourne Stoke area.
“We sent three double-crewed land ambulances, an air ambulance and an operations officer.
“We are conveying three patients to Salisbury District Hospital by land ambulance.”
