Systematic Investment Plan
Also written SIP · Systematic Investment Plan (SIP) · Rupee cost averaging
A facility to invest a constant amount into a scheme at regular intervals, which buys more units when the NAV is low and fewer when it is high and so averages the cost of acquisition down.
In plain language
An SIP fixes the rupees, not the units. Rs 10,000 a month buys whatever that money buys on the date it is invested — a lot of units when the market is down, fewer when it is up.
That asymmetry is the entire mechanism, and it works in the investor's favour automatically. The cheap months buy more units than the expensive ones, so the average cost of acquisition ends up below the simple average of the NAVs on the transaction dates. This is rupee cost averaging, and it requires no forecast of any kind.
The second benefit is behavioural and probably larger. Investing Rs 10,000 every month is a decision made once. Investing Rs 1,20,000 in one go is a decision an investor postpones when markets are falling, which is precisely when they should not.
How it works
An SIP can open a fresh folio or add to an existing one, and the minimum to start one is typically lower than for a lump-sum purchase. It can even be started during a New Fund Offer. Instalments are collected through NACH, standing instructions or post-dated cheques, so the transaction executes without the investor having to act each month — which the workbook describes as protecting the portfolio from investor inertia.
Stamp duty applies to every instalment. Since 1 July 2020, units issued against any purchase — lump sum, SIP, STP, switch-in or IDCW reinvestment — attract stamp duty at 0.005% of the amount invested, and units are allotted only on the amount left after it. On a Rs 10,000 instalment that is 50 paise.
A distributor bringing in an eligible new investor through SIP earns additional commission of 1% of the total investment made during the first year, capped at Rs 2,000, under SEBI's framework for new individual investors from B-30 cities and new women investors.
The formula
Units allotted in a month = Instalment ÷ NAV on the transaction date
Average cost per unit = Total amount invested ÷ Total units accumulated
Rupee cost averaging is the observation that:
Average cost per unit < Simple average of the NAVs
whenever the NAV varies at all.
A worked example
An investor runs Rs 10,000 a month into an equity scheme for six months through a market dip.
| Month | NAV (Rs) | Units allotted |
|---|---|---|
| 1 | 42.00 | 238.095 |
| 2 | 38.50 | 259.740 |
| 3 | 35.00 | 285.714 |
| 4 | 39.20 | 255.102 |
| 5 | 44.00 | 227.273 |
| 6 | 46.50 | 215.054 |
| Total | 1,480.978 |
Total invested = Rs 60,000
Average cost per unit = 60,000 ÷ 1,480.978 = Rs 40.51
Simple average of NAVs = 245.20 ÷ 6 = Rs 40.87
The units were acquired 36 paise below the average NAV, without a single judgement about the market. Month 3 is where it happened: the cheapest NAV bought the most units.
Value the holding at month 6, when the NAV is Rs 46.50:
| Units | Value at Rs 46.50 | |
|---|---|---|
| SIP of Rs 10,000 × 6 | 1,480.978 | Rs 68,865 |
| Lump sum of Rs 60,000 at month 1 (NAV 42.00) | 1,428.571 | Rs 66,429 |
The SIP is Rs 2,436 ahead — because the market fell before it rose. Reverse the path and put the same six NAVs in ascending order, and the lump sum wins. Rupee cost averaging lowers the average cost; it does not promise to beat a lump sum.
(Each Rs 10,000 instalment actually buys units worth Rs 9,999.50 after stamp duty of 0.005%; the table ignores that rounding.)
Why NISM asks about it
Chapter 9 (Investor Services), section 9.11.1, introduces the SIP and works the rupee-cost-averaging arithmetic; Chapter 8 adds the stamp duty, and Chapter 6 the distributor commission. Expect a computation asking for units allotted at given NAVs or for the average cost, plus recall questions on which transactions attract stamp duty and how the ELSS lock-in works on a SIP.
Common exam traps
- SIP is a facility, not a product. It is a way of investing into a scheme, not a scheme, an asset class or a separate category of fund.
- Rupee cost averaging lowers the average cost below the average NAV — that is all it guarantees. It does not guarantee a profit and does not always beat a lump sum; in a market that only rises, the lump sum wins.
- Every instalment attracts stamp duty at 0.005%, and so do STP instalments, switch-ins and IDCW reinvestments. Units are allotted net of it.
- In an ELSS, each instalment is locked in for three years from its own date. The whole SIP does not unlock three years after the first instalment.
- Each instalment is a separate purchase with its own date, which is what drives both that lock-in and the holding-period test for capital gains.
- A SIP can be started in an NFO — a point the workbook makes explicitly and questions like to test.
Where this is taught
- Series V-D · Chapter 9: Investor Servicesintroduced here
- Series V-A · Chapter 9: Investor Servicesintroduced here
- Series II-B · Chapter 14: Financial Transactionsintroduced here
- Series SEBI-ICE · Chapter 5: Investment in Securities Marketintroduced here
Related terms
- ELSSEquity Linked Savings Scheme — an open-ended equity scheme with a statutory lock-in of 3 years and tax benefit, minimum 80% in equity, offering deduction of up to ₹1,50,000 a year under Section 80C of the Old Tax Regime.
- New Fund OfferThe period in which a mutual fund scheme's units are offered to the public for the first time, at a fixed NFO price rather than at NAV, and during which the registrar builds the scheme's first register of investors.
- Stamp dutyPayable at 0.005 per cent — Rs. 5 per lakh — on all mutual fund transactions since July 2020, covering equity, debt and exchange traded funds and all modes including SIPs and STPs, but imposed only on the purchase of…
- Systematic Transfer PlanA standing instruction to move a fixed amount from one scheme into another of the same mutual fund at a set frequency — a withdrawal plan out of the source and a SIP into the target.
- Systematic Withdrawal PlanA standing instruction to redeem a set amount — or only the appreciation — from a mutual fund scheme at a chosen frequency, used to manufacture a regular income in retirement.
- One-Time MandateA standing authorisation to a bank to honour debits raised by a mutual fund through NACH, registered at folio level, taking three to four weeks to set up and allowing an "as and when presented" option within a specified…
- Mutual fundA trust registered with SEBI that pools money from many investors and invests it in securities on their behalf — not a different product from shares and bonds, but a different way of owning them.
- Consolidated Account StatementA single statement showing an investor's transactions and holdings across every scheme of every mutual fund in India, linked by PAN and issued monthly where there has been a transaction.
- Financial planningThe process of estimating what a person will need money for across their lifetime and building an investment plan to meet each of those needs — savings with a purpose attached.
- Capital appreciationThe gain made when the market value of an investment rises above what you paid for it — as distinct from income, which is the interest or dividend the investment pays you along the way.