It is narrated from Sayyiduna Awf bin Malik (may Allah be pleased with him) that whenever fay' (wealth obtained without fighting) came to the Prophet (peace and blessings be upon him), he (peace and blessings be upon him) would distribute it on that same day.
Hadith Referenceالسنن الكبرى للبيهقي / كتاب قسم الفيء والغنيمة / 13026