When should the fasting fidyah be paid by the elderly and by patients with no hope of recovery, and can it be paid in one go before Ramadan?

Summary

An elderly person unable to fast, or a patient with no hope of recovery, may pay fidyah on the day of the missed fast or delay it to another day. According to the Shafi'i school, it may be paid from dawn of that day, may be brought forward to the preceding night before dawn, and may be postponed until the end of Ramadan. Paying promptly is encouraged because delay may result in it not being fulfilled. Paying fidyah for the whole month before Ramadan is haram, since the obligation has not yet arisen. The fatwa likens this to zakat, which may not be paid in advance for two years at once, and paying zakat two days or more early is also haram.

Written in our own words from the original fatwa — check the source before acting on it.