what is the minimum distance at which you must switch your high beams to headlights?

The minimum distance at which you must switch your high beams to low beam headlights is generally 200 meters. This applies both when approaching an oncoming vehicle and when following another vehicle. Switching at this distance helps prevent dazzling other drivers and ensures road safety. This 200-meter rule is widely followed in places like Australia and is recommended as a best practice for safe driving at night or in low visibility conditions.