Demystifying the Cost of Acquisition for Bonus Shares

Imagine you are drafting an internal advisory report for a high-net-worth client who has held equity in an IT firm for over a decade. The company recently declared a 1:1 bonus issue, and the client asks you how this impacts their future capital gains liability when they decide to trim their position.

While the market sees this as a ‘free’ distribution of wealth, your role as an analyst is to move beyond the market sentiment and accurately calculate the tax base for these instruments. A fundamental misunderstanding of the cost of acquisition here can lead to a significant overstatement of gains and, consequently, an erroneous tax projection for the client.

In the Indian tax regime, the cost of acquisition for bonus shares is strictly defined as nil. This is because the shareholder has not made any additional capital outlay to acquire these shares; they are essentially a capitalization of the company’s existing reserves. When you compute the capital gains upon disposal, you are effectively taking the full sale proceeds—minus any incidental costs like brokerage or securities transaction tax—as the taxable profit.

This differs sharply from the original underlying shares, where you would deduct the actual purchase price from the sale proceeds to arrive at the capital gain.

Consider an analyst modeling a portfolio exit strategy where the client holds 1,000 original shares purchased at ₹500 each and receives 1,000 bonus shares. If the shares are sold at a market price of ₹1,200, the tax treatment for the two tranches is bifurcated. For the original shares, the cost of acquisition is ₹500, yielding a gain of ₹700 per share. For the bonus shares, the cost of acquisition is zero, meaning the entire ₹1,200 is treated as a gain.

Failing to account for this ’nil’ cost in your spreadsheet models will result in an artificially inflated net-of-tax return estimation, potentially misleading the client about their liquidity after tax.

This distinction matters because it impacts the net cash flow realization for the client. When you are performing valuation or tax-planning exercises, you must ensure that your model treats bonus shares as distinct tax lots with a zero cost base. This rigor is essential for providing accurate recommendations, as it highlights the reality that bonus issues do not just shift share prices; they shift the tax architecture of the investment itself.

Professional advisory requires that you communicate this clearly to ensure the client understands that while their equity base has doubled, their tax liability per share has effectively increased due to the zero-cost basis of the bonus portion.¹

Nuance

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This is a companion read for Section 13.1 — Taxation of Bonus Shares from PASS Investment Adviser (Level 2) by Akhilesh Gururani, available on Amazon Kindle.

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