Stamp Duty Impact on SIP
The stamp duty on mutual fund transactions, introduced at 0.005% on purchase transactions (including SIP instalments) effective July 1, 2020 under an amendment to the Indian Stamp Act, 1899, represents a small but permanent drag on compounding returns for systematic investors, with its long-term impact amplifying over decades due to the mathematics of compounding on reduced principal.
Prior to July 2020, mutual fund purchases attracted no stamp duty in most states. The Finance Act 2019 amended the Indian Stamp Act to impose a uniform 0.005% stamp duty on all mutual fund purchase transactions, including each SIP instalment, switch-in transaction, and lump-sum purchase. On a Rs 10,000 SIP instalment, the stamp duty amounts to Rs 0.50 — a seemingly trivial figure. The unit allotment is computed on the net amount after stamp duty deduction, meaning slightly fewer units are allotted than a pre-duty calculation would suggest.
The compounding drag from even a sub-penny charge per rupee becomes meaningful at scale and over long horizons. A Rs 10,000 monthly SIP maintained for 30 years at 12% CAGR accumulates to approximately Rs 3.5 crore without stamp duty. With a 0.005% deduction on each instalment, the effective monthly investment is Rs 9,999.50 — and the long-term corpus is reduced by approximately Rs 1,750. While this absolute figure may appear modest, the drag arises not from the stamp duty amount alone but from the concept of basis cost compression: every re-investment is also subject to the duty, making the effective drag slightly higher than a naive calculation on just the initial instalments suggests.
Stamp duty applies to all purchase transactions regardless of plan type (direct or regular), fund type (equity, debt, or hybrid), or investment route (SIP, STP, lump sum, or dividend reinvestment). Redemption transactions and SIP cancellations do not attract stamp duty. The collected stamp duty is remitted to state governments based on the address of the investor — with states applying the central rate uniformly following the constitutional amendment that enabled the stamp duty reform.
From an investment decision standpoint, the 0.005% stamp duty is negligible in isolation but interacts with other cost components including the expense ratio (typically 0.10-1.70% per annum for equity funds) and exit load (typically 1% for redemptions within 12 months). The total cost of investing, inclusive of stamp duty, expense ratio, and any distributor commission embedded in the regular plan TER, determines the net return to the investor relative to the gross portfolio return. Direct plan investors eliminating the distributor trail commission save substantially more — often 0.5-1.0% per annum — than the stamp duty costs, reinforcing the financial logic of direct plan investing for self-sufficient or advisor-supported investors.
For high-frequency institutional investors who make large daily or weekly mutual fund transactions for treasury management — particularly corporates using liquid funds as a cash equivalent — the stamp duty has a more pronounced cumulative impact due to the high transaction frequency. An institution executing Rs 100 crore in daily liquid fund purchases incurs Rs 50,000 per day in stamp duty — approximately Rs 1.25 crore per annum — a meaningful reduction in the effective yield from liquid fund investments compared to direct overnight or T-Bill investments that do not attract stamp duty.