Question:
Is it permissible to delay the missed fasts of Ramadan until the winter season?
Answer:
Once the excuse (such as illness, pregnancy, or travel) preventing a person from fasting is removed, it becomes obligatory to make up the missed fasts as soon as possible. Unnecessarily delaying the missed fasts is not allowed, as one may face unforeseen circumstances such as illness, travel, or even death.
However, if a person chooses to delay making up the fasts until winter, when the days are shorter and fasting is easier, it is permissible, and the obligation of Qada (making up the fasts) will be fulfilled.
(Shaykh Ibn Jibreen – رحمه الله)