If tax does not calculate on secondary item at the time of billing then this issue can easily be resolved in Marg Software:

In order to resolve this issue, the user needs to follow the below steps:

• Firstly, Go to Masters >> Marg Setups >> Control Room.

• A 'Control Room' window will appear.

• The user will select ‘Search in all’. Press 'Enter'.

• A 'Controls' window will appear then the user will search 'Secondary Tax'.

• Now click on ‘Accept’.

• A 'Secondary Tax' window will appear.

• In 'Tax calculate on Secondary Items in Sales Bills' option, the user will select 'Y'.

• The user will now press 'Esc' key twice.

• Now click on ‘Yes’ to save the changes.

After following the above steps, Tax will be calculated on secondary items while billing.