TallyPrime Multi-HSN Customization

I’m running TallyPrime and all of my stock items are already organised by product type. The challenge is that some products need more than one HSN code, depending on where or how they are dispatched, yet I still want to keep a single master item to preserve clean inventory figures.

What I need built is a simple, fool-proof way to store and recall multiple HSN codes inside one stock item and then have the correct code flow automatically into every relevant document—purchase, sales, delivery note, GST reports—without forcing us to duplicate the item itself. Usability is important: staff should be able to pick the right HSN at voucher entry (or have it driven by a rule such as customer class), and the system must respect all of TallyPrime’s native tax calculations.

Acceptance criteria
• One stock item can hold two or more HSN codes.
• At voucher time the intended HSN can be selected or auto-applied, and the chosen code prints on invoices and populates GST returns.
• No loss of existing batch, MRP, or stock ageing data.
• Works entirely inside TallyPrime (no external Excel macros).

If you’ve created similar TallyPrime customisations—especially using TDL—let’s discuss your approach and timeline.