Prayer: Journey Less Than Eight Farsakhs or Doubting the Distance
Practical Laws of Islam as per the teachings of Ayatullah Sistani
Ruling 1260
If a person’s journey is a little short of eight farsakhs, or if he does not know whether or not his journey is eight farsakhs, he must not perform qaṣr prayers. In the event that he doubts whether or not his journey is eight farsakhs, it is not necessary for him to investigate and he must perform tamām prayers.