Is it permissible to pay their zakat in advance before the completion of their zakatable year ?
Is it permissible for a person to pay their zakat in advance before the completion of their zakatable year? For example: Zaid’s date to discharge his zakat is Muharram 1st. Before the completion of a year (i.e. before the arrival of next year’s Muharram 1st), he discharges his zakat. Answer: ﺑﺴﻢ اﷲ اﻟﺮﺣﻤﻦ اﻟﺮﺣﯿﻢ In the name of Allah, the Most Gracious, the Most Merciful
Yes, it is permissible to pay your zakat in advance irrespective of the number of years (i.e. there is no restriction on how many years you pay in advance). However, paying zakat in advance will only be permissible on the condition that you possess nisab (amount of wealth which makes zakat obligatory). 
Only Allah knows best
Written by Maulana Mohammad Ahsan Osmani Checked and approved by Mufti Mohammed Tosir Miah Darul Ifta Birmingham
 Sharhul Wiqayah: v. 2, p. 437-438 (Qadeemi Kutub Khana); Al- Lubab fi Sharhil Kitab: v. 1, p. 146 (DKI); Athmarul Hidayah: v. 2, p. 446 (Zam Zam)