The Ruling on an Elderly Woman Who Is Unable to Fast

Question:
Your Eminence the Shaykh, my question, may Allah preserve you, is about an elderly woman who is unable to fast, such as the fast of Ramadan, due to illness and old age. Is it better that she fast on her behalf if possible, or that she pay expiation? May Allah preserve you.

Answer:
The one who is unable to fast due to old age or a chronic illness that is not expected to be cured, and cannot make up the fast, owes fidyah (a ransom payment). He feeds one poor person for every day, the amount being half a sa' (a dry measure of about 3 kg), which is one and a half kilograms per day. He does not fast on his behalf; the fidyah is sufficient, and this fidyah suffices in place of the fast.