Call Centre services come under the category of Business Auxiliary Services. Call Centre Services were fully exempted from levy of service tax w.e.f. 1st July, 2003, vide notification No. 8/2003-Service Tax, dated 20th June, 2003. But this exemption was rescinded vide Notification No.2/2006 – ST dated 1.03.2006.
But as per Rule 3(1)(iii) of Export of Service Rules, 2005 - "Export of taxable services shall, in relation to taxable services‚ specified in clause (105) of section 65 of the Act, (excluding some services) when provided in relation to business or commerce, be provision of such services to a recipient located outside India and when provided otherwise, be provision of such services to a recipient located outside India at the time of provision of such service."
Hence, even though the exemption provided to call centres has been withdrawn, where Call Centre Services are provided to Recipients located outside India, it should be considered as Export of Service under the above said Rules and hence no service tax is payable.
Further as per section 69 of Finance Act, 1994 - Person liable to pay Service Tax has to apply for Registration. In case one is not required to pay service tax, it seems registration is also not required.