What is the ruling on fasting on Fridays?

It is considered as makruh tanzihi to perform nafl fast only on Fridays. The Prophet (saw) said, “None of you must fast on Friday unless he fasts the day before or the day after.” (Abu Dawud, Sawm, 50). It is permissible to fast on Friday to make up a missed fardh fasting or to fulfill a wajib fasting such as a votive fasting. It is permissible to fast before or after Friday for those who want to fast on Friday. The reason why fasting only on Friday is makruh is because Friday is considered the weekly eid for Muslims.

Source: Presidency Of Religious Affairs The Turkey, High Board of Religious Affairs FATWAS,

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