If you're putting ELSS money in between January and March, lump sum and SIP are nearly the same thing: with three months left, a "SIP" is just two or three instalments. Over long periods the gap between the two is small; the bigger questions are whether the old regime suits you and how much of your ₹1.5 lakh is already used.
Every year, salaried investors in the old tax regime find they have not used their ₹1.5 lakh deduction and rush money into ELSS (tax-saver) funds before March. This guide explains how each approach works, what the lock-in means for each, what real fund history does and does not show, and what to check first. It is written for tax year 2026-27 (1 April 2026 to 31 March 2027).
An earlier version of this article included a 15-year backtest whose numbers could not be reproduced. It has been removed. The only historical figures below come from AMFI NAV data and NSE index data, with dates.
The Short Answer
- Lump sum puts all your money in the market sooner. If markets rise afterwards, it usually ends ahead. If they fall, it ends behind.
- SIP spreads your entry price over several months. It reduces the risk of investing everything just before a fall, at the cost of keeping money out of the market for longer.
- Over long periods the gap is usually small, and which one "wins" depends mainly on timing assumptions, not on a reliable rule.
- In January to March you cannot really do a SIP. With at most three months left, a "SIP" is just two or three instalments. The real SIP decision is made in April.
- The bigger questions are whether the old regime suits you at all, and how much of your ₹1.5 lakh is already used by EPF, PPF, insurance premiums or home-loan principal.
ELSS Tax Rules for Tax Year 2026-27
- Deduction: up to ₹1.5 lakh a year under section 123 of the Income-tax Act, 2025 (the old section 80C). The ₹1.5 lakh is shared with other eligible items such as EPF, PPF, life insurance premiums, children's tuition fees, home-loan principal and NSC.
- Old regime only: the deduction is not available if you choose the new tax regime.
- Deadline: to count for tax year 2026-27, the money must be invested by 31 March 2027.
- Lock-in: 3 years from the date of each investment, not from the date you file your return.
- Maximum tax saved: ₹46,800 a year, if you are in the 30% slab (₹1.5 lakh × 30% plus 4% cess, or 31.2%).
- Tax when you sell: ELSS units are always held over 12 months by the time you can sell them, so gains are long-term. They are taxed at 12.5% on gains above ₹1.25 lakh a year across your equity investments, under section 198 (old section 112A).
Income for the year ended 31 March 2026 (FY 2025-26) is still filed in 2026 under the old Income-tax Act, 1961, where the same ₹1.5 lakh deduction sits under section 80C.
How the lock-in works for each SIP instalment
Each SIP instalment is a separate purchase with its own 3-year lock-in. If you invest ₹12,500 a month from April 2026 to March 2027:
- The April 2026 instalment can be redeemed from April 2029.
- The March 2027 instalment can be redeemed only from March 2030.
A single lump sum invested on, say, 15 February 2027 unlocks in full on 15 February 2030. So a SIP staggers your unlock dates across a year, while a lump sum frees everything on one day. Neither matters much if you plan to hold for many years, but it matters if you need the money soon after the lock-in ends.
First Check: Is the Old Regime Worth It for You?
ELSS only saves tax in the old regime. For tax year 2026-27 the new regime is the default. It offers a ₹75,000 standard deduction (₹50,000 in the old regime) and a rebate that leaves taxable income of up to ₹12 lakh free of tax. Many salaried people now pay less under the new regime unless they have large deductions such as HRA, home-loan interest and the full ₹1.5 lakh.
Run your own numbers in our tax saving calculator before you invest anything for tax reasons, and see our old vs new regime guide. If the new regime is better for you, an ELSS is just an equity fund with a 3-year lock-in. You may prefer a fund without one.
How Lump Sum and SIP Differ
| Lump sum | SIP (monthly) | |
|---|---|---|
| Time in the market | All money invested from day one | Money goes in gradually; the rest waits in your bank account |
| Entry price | One price, good or bad | An average of several prices |
| Does better when | Markets rise soon after you invest | Markets fall or swing soon after you start |
| Cash needed | ₹1.5 lakh at once | ₹12,500 a month for a full year |
| Lock-in | Everything unlocks on one date | Each instalment unlocks 3 years after it was invested |
| Effort | One transaction | Set up once, then automatic |
An Illustrative Example (Not Historical Data)
The NAVs below are made up to show the mechanics. They are not real fund prices. You invest ₹1.5 lakh either as one lump sum in January, or as ₹50,000 each in January, February and March. Both are valued at the NAV on 31 March.
| Scenario (NAV Jan / Feb / Mar / 31 Mar) | Lump sum units | Lump sum value | 3 instalments: units | 3 instalments: value |
|---|---|---|---|---|
| Rising: 100 / 104 / 108 / 110 | 1,500.0 | ₹1,65,000 | 1,443.7 | ₹1,58,811 |
| Falling: 100 / 92 / 88 / 90 | 1,500.0 | ₹1,35,000 | 1,611.7 | ₹1,45,049 |
| Dip and recover: 100 / 90 / 100 / 102 | 1,500.0 | ₹1,53,000 | 1,555.6 | ₹1,58,667 |
How the numbers work: the lump sum buys ₹1,50,000 ÷ 100 = 1,500 units. In the falling case, the instalments buy 500 + 543.5 + 568.2 = 1,611.7 units, an average cost of about ₹93 a unit. Value = units × the 31 March NAV.
The lump sum wins when prices rise after you invest, and staggered buying wins when they fall or dip. Nobody knows in January which path the next three months will take.
What Real ELSS History Shows
We re-ran the comparison on actual AMFI NAV data for six ELSS funds that have history back to 2008: HDFC, SBI, Franklin India, Quant, DSP and ICICI Prudential ELSS, using their Regular Growth plans because Direct plans only began in January 2013. The funds were chosen only for the length of their history; this is not a ranking. Each investor put in ₹22.5 lakh over 15 years:
- Lump sum: ₹1.5 lakh on 15 February each year.
- SIP: ₹12,500 on the 7th of every month through the same financial years (April to March).
- Both valued on 15 February of the final year.
| 15-year window | Lump sum corpus (6 funds) | SIP corpus (6 funds) | Result |
|---|---|---|---|
| FY 2008-09 to Feb 2024 | ₹0.88–1.38 crore | ₹0.88–1.36 crore | Near tie: SIP ahead by up to 1.4% in five funds, lump sum ahead by 1.2% in one |
| FY 2009-10 to Feb 2025 | ₹0.77–1.09 crore | ₹0.83–1.12 crore | SIP ahead by 3.3–7.2% in all six |
| FY 2010-11 to Feb 2026 | ₹0.77–1.15 crore | ₹0.81–1.17 crore | SIP ahead by 2.1–5.0% in all six |
Two points matter more than the winner:
- The gap between funds was far bigger than the gap between methods. In each window the best fund ended with about ₹29–50 lakh more than the weakest one. Lump sum vs SIP moved the result by a few per cent.
- The result flips with the timing assumption. If the SIP instead starts in February, alongside the first lump sum, the lump sum wins every window by 4.7–13.6%, simply because more of its money is invested earlier. A late-February lump sum is compared here with a SIP that started ten months earlier, which is what gave the SIP its edge.
Past results like these do not predict the future. To test any specific fund on real NAV history yourself, use our SIP vs lumpsum calculator, which backtests both methods on actual AMFI NAVs over 1, 3, 5 or 10 years. Pick a fund that has existed for the whole period you test.
Is February a bad month to buy?
There is no reliable seasonal pattern to exploit. The Nifty 50 Total Return Index rose in February in 8 of the 20 years from 2007 to 2026, with an average February return of about −1.4% (NSE Indices data). That is a small, noisy sample, not a reason to avoid or prefer February.
When Each Approach Makes Sense
A SIP tends to suit you if
- You are planning at the start of the tax year, in April, and can spread ₹12,500 a month across twelve months.
- Your tax-saving money comes out of monthly salary rather than a bonus.
- You would worry about investing everything just before a fall.
- You want staggered unlock dates after the lock-in.
A lump sum tends to suit you if
- The money already exists, for example a bonus, and would otherwise sit idle for months.
- It is late in the year and too few months remain for a meaningful SIP.
- You are comfortable with a single entry price and a long holding period.
Do not borrow or break a fixed deposit early just to make an ELSS deadline. The penalty or interest can cancel out much of the tax saved.
A Practical Plan for the Rest of Tax Year 2026-27
- Confirm your regime. If you will choose the new regime, ELSS gives you no deduction.
- Work out how much room is left. Subtract your EPF contribution, PPF, life insurance premiums, tuition fees and home-loan principal from ₹1.5 lakh. Only the remainder needs to go into ELSS for tax purposes.
- Spread what is left over the months remaining. If you start in October 2026, six monthly instalments of ₹25,000 reach ₹1.5 lakh by March 2027. If you start in January 2027, three instalments of ₹50,000 do.
- Choose a direct plan. A direct plan has a lower expense ratio than the regular plan of the same fund. If the regular plan costs 0.5–0.8% a year more, ₹1.5 lakh a year for 20 years at a 12% gross return ends roughly ₹7.3–11.5 lakh lower. Our direct vs regular guide explains the difference.
- Set an April reminder to start next year's SIP at the beginning of the tax year, so you are not rushing again next January.
What to Check Before Choosing an ELSS Fund
- Treat it as an equity fund first. Your money is locked for 3 years and exposed to stock-market swings. Choose a fund you would hold even without the tax benefit.
- Look at long-period returns against the benchmark, not the last year. Check 5-year and 10-year figures from the fund's factsheet, with the as-of date.
- Compare total expense ratios of the direct plans.
- Test the fund's own history. Run it through the SIP vs lumpsum backtest for 5 or 10 years to see how both methods actually played out on its NAVs.
- Compare ELSS with the alternatives. PPF and NPS also give tax benefits, with different risk, lock-in and tax on withdrawal. Our ELSS vs PPF vs NPS calculator compares them side by side.
- Know how it compares with a plain index fund. See index funds vs ELSS for tax saving.
For the rest of your year-end tax steps, see our tax planning checklist.
This article explains how ELSS lump-sum and SIP investing work. It is not a recommendation to buy any fund. The illustrative example uses made-up prices. Historical results are based on past NAV data and do not guarantee future returns.