Making up for some Ramadan days only discharges the obligation of the missed Ramadan fasts
Q: It is claimed, and only Allah knows the truth, that if
a woman is duty-bound to make up for a number of Ramadan missed fasts, it is permissible for her, while embarking upon the recommended fast of the six days of Shawwal,
to say: "O Allah, I intend both obligatory and supererogatory fasts". What is the Shari`ah (Islamic law) ruling on this?
Making up for some Ramadan days only discharges the obligation of missed Ramadan fasts; thus, it is impermissible to combine another kind of fast with it through one intention. However, it is Mustahab (desirable) and an abundantly deserving reward to fast the supererogatory six days of Shawwal after making up for the missed fasts of Ramadan. Anyway, the above-quoted saying has no basis in Shari`ah. (Part No. 9; Page No. 276) May Allah grant us success. May peace and blessings be upon our Prophet Muhammad, his family, and Companions.