Fiqh-us-Sunnah Volume 3, Zakaat and Fasting, Fiqh 3.090.
Section : Distribution of Zakat ul-Fitr.
The distribution of zakat ul-fitr is the same as that of zakah– that is, it has to be distributed to the eight groups of beneficiaries mentioned in the ‘ayah: “The alms are only for the poor …” [atTaubah 60]. The category comprising the poor is considered the most deserving. This is also supported by the hadith: “The Messenger of Allah, upon whom be peace, enjoined zakat ul-fitr as a purification for the one who fasts from any indecent act or speech, and as food for the needy.”
Al-Baihaqi and ad-Daraqutni relate from Ibn ‘Umar who said: “The Messenger of Allah, upon whom be peace, enjoined the zakat ul-fitr, and also said: ‘Free them from want on this day.'”