The inauguration of new presidents in the Islamic Republic typically occurs in early August, although no specific date is set. However, since there is currently no incumbent in office, there is some debate about when the new administration will officially begin.
The only timeframe that applies in case of the death of a president is 50 days until a new one should be elected. Raisi died in a helicopter crash on May 19, and the election was held on June 28 and the runoff on July 5.
There are several steps until the president-elect can be called Iran’s President.
After the election, the Guardian Council should confirm the validity of the results, ensuring that the election process followed legal precepts. Then, it issues a certificate of appointment for the president-elect. This document should be signed by the members of the Council and then sent to the Supreme Leader, who would announce the date for Tanfiz, when he officially endorses the election results and ratifies the new president. It is followed by Tahlif, or the swearing-in ceremony, which usually happens within a few days.
During the Tanfiz, Ali Khamenei hands over a decree, known as the "decree of confirmation" or "decree of validation", to the president-elect, formally recognizing him as the legitimate president. Without the Supreme Leader's approval, the president does not have the authority to assume office. During Tahlif, the newly elected president takes an oath before the Parliament (Majlis) in the presence of the head of the judiciary and the members of the Guardian Council, promising to uphold the constitution and faithfully execute his duties as the head of state. Both ceremonies are essential in the transition of presidential power, ensuring both legal and symbolic legitimacy for the incoming president.