How this calculator works
When a company issues bonus shares, it capitalizes part of its reserves into new shares, allotted free to existing shareholders in a fixed ratio. This calculator applies the standard value-preserving math behind a bonus issue:
Bonus shares = Shares held × (new ÷ held), so a 1:1 ratio gives you one extra share for every share you already own.
Total shares after = Shares held + Bonus shares.
New price per share = (Shares held × Current price) ÷ Total shares after — the market capitalizes the same total value across a larger number of shares, so the per-share price adjusts down proportionally. Your total holding value stays the same immediately after the bonus issue; only the number of shares and the per-share price change.
Worked example
100 shares held at ₹500 each, with a 1:1 bonus issue: bonus shares = 100 × (1÷1) = 100. Total shares after = 100 + 100 = 200. New price per share = (100 × ₹500) ÷ 200 = ₹250.00. Total value before (100 × ₹500 = ₹50,000) equals total value after (200 × ₹250 = ₹50,000) — unchanged.
Bonus issues change your cost basis per share — Shunya's CA team can help you work out the correct tax treatment when you eventually sell.
Talk to a CA →Is a bonus share the same as a dividend?
No — a bonus issue capitalizes reserves into more shares, it isn't a cash payout, and unlike dividends it isn't taxed as income at issuance.
Does my total investment value change after a bonus issue?
No, same logic as a stock split — more shares at a proportionally lower price, same total value.
How is the cost basis split for tax purposes?
Your original cost basis gets spread across the new total share count — for capital gains tax when you eventually sell, consult your CA for the exact per-share cost basis calculation, don't compute it here.
This tool is for quick estimation only and is not a substitute for professional tax or investment advice. For your specific situation, consult a practicing CA.
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