When the service tax details are defined in the stock item/group level, the service tax rate, if defined at the company or master level will be over-ridden.
To define service tax details
1. Go to Gateway of Tally > F11: Features > Statutory & Taxation.
2. Set Enable service tax? to Yes.
3. Set the option Set/alter service tax details? to Yes. The Service Tax Details screen appears.
4. Set Enable service tax details for stock groups/items? to Yes to enable service tax details in the stock item/group level.
5. Press Enter to save.
For step-by-step produce to create a stock item with service tax details, refer Creating Stock Item and Creating Stock Group.
Defining Service Tax Rate at Company Level
Defining Service Tax Rate at Ledger Level