01 March 2012
If you pay service tax through internet banking, the due date is 6th of every month. In case service tax is deposited through cheque to bank, due date is 5th of every month.
For interest, if you pay service tax on 07th through internet banking, you have to pay interest for one day i.e. from 06th. In another case of manual payment, interest shall be charged for two days from 5th.
Interest for one day = total service tax x 18% / 365
This is the calculaton method which can be used for work out interest.