Muhaqqaq Masala

Paying extra Zakat by mistake.

If the obligatory amount of Zakat payable by a person is small, and he mistakenly paid more Zakat, then there is an allowance for him to count this excess amount towards the Zakat of the coming year. And if he considers this excess amount as voluntary charity (Nafl Sadaqah), and pays the Zakat of the next year at its due time by calculating it separately, even then there is no harm; rather, this is a cause for greater virtue. (Aham Masail/Vol:3/Page:138)