Sayyiduna Ali bin Abi Talib (may Allah be pleased with him) said that Abbas bin Abd al-Muttalib (may Allah be pleased with him) asked the Messenger of Allah (peace and blessings be upon him): Can zakah be given before the year has passed? And he (peace and blessings be upon him) granted him permission.
Hadith Referenceالسنن الكبرى للبيهقي / كتاب الأيمان / 19966