Service tax under reverse charge

ankit jain (Semi-Qualified) (36 Points)

02 November 2016  
I have made an advance payment of work contract on which reverse charge is applicable. Whether i should pay service tax on advance payment amount or full bill amount. For Example, Bill amount is Rs. 250000 which will be raised on 15/12/2016 and today on 02/11/16, i have to pay Rs. 100,000 as advance. Please help me, what amount should be paid as service tax under reverse charge.