Abu Dawud Book 3, Hadith Number 1605.
Chapter : Not known.
Narated By Abdullah ibn Abbas : The Apostle of Allah (PBUH) prescribed the sadaqah (alms) relating to the breaking of the fast as a purification of the fasting from empty and obscene talk and as food for the poor. If anyone pays it before the prayer (of ‘Id), it will be accepted as zakat. If anyone pays it after the prayer, that will be a sadaqah like other sadaqahs (alms).