There is no employer's "contribution" to profession tax. Certainly, based on the revenue (turnover) received by the employer, he is supposed to "pay" profession tax.
Profession Tax is decided according to a slab fixed by the State Government. The same slab is applicable to employees of any establishments, self-employed professionals, and others. Normally, the said slab will remain in force for many years, and there is no financial year prescribed for profession tax. PT is payable for every half-year. For details and slab for PT, please refer to the relevant Act in Tamil Nadu.
Regards,
Madhu.T.K