Service tax query urgent

A Sharma (Marketing ) (24 Points)

16 December 2013  

I have an urgent query. Hope somebody can help. I have learnt that once a company touches a turnover of 9 lakh, it registers for a service tax number and when it crosses 10 lakh, it needs to file the service tax. My query is whether one is required to file the service tax only for the transactions which take place AFTER a company has registered for a service tax number or are we required to pay the service tax for all previous transactions which ever happened (even before the company touched the 9 lakh limit) 

Thanks in advance :)