ST payment liability in your cases arises when the payment is received. As u said the payment will be received in April 2010 then the ST liability shall arise in that month only & the due date shall be 5th July 2010 if the assessee is individual, HUF.or partnership. Howver if the assessee is other then the aforementioned, then the due date of payment is 5th May 2010. Refer table given below:
Payment of service tax:
(a)Service tax payable by Individuals, Proprietary concern, Partnership firms
Payable on amounts received during the quarter
Due Date
Manual
E – Payment
1st April to 30th June
5th July
6th July
1st July to 30th Sept.
5th October
6th October
1st Oct. to 31st Dec.
5th January
6th January
1st Jan. to 31st March
31st March
31st March
(b)Service tax payable by Corporate entities, Trusts, Institutions & Societies & so on.