Lumpsum or SIP for Your Bonus: Invest ₹5 Lakh in One Go or Spread It?

The bonus credit came through this morning, bigger than last year, or a plot your father bought in the nineties has finally sold. Either way there is ₹5 lakh sitting in the savings account, and everyone has an opinion. The bank RM wants a "one-time premium" plan, a colleague says put it all in a fund today, and your gut says the market is at a high, so wait.

The question underneath is simple: invest the whole amount in one go, or spread it out over a few months? The honest answer is that one go usually wins on paper, spreading out usually wins on sleep, and there is a sensible middle path that most people should take. Below are the rupee numbers for each, and at the end two made-up people with very different bonuses work it through.

Lumpsum, SIP and STP: three ways to put a bonus in

Lumpsum means the full ₹5 lakh goes into a mutual fund on one day. You get that day's NAV, and from then on the whole amount rides the market.

Spreading it as a SIP means you keep the money in your savings account and invest, say, ₹41,667 a month for 12 months. It works, but the waiting money earns only savings-account interest, about 2.5–3% at most big banks, and it is very easy to "borrow" from it for a phone or a trip.

STP (systematic transfer plan) is the tidier version of the same idea. You put the full amount into a liquid fund (or another low-risk fund) and give the fund house a standing instruction to move a fixed amount into an equity fund every week or month. Both funds have to be with the same fund house. The waiting money earns liquid-fund returns, which have been roughly 6% over the past year, and the transfers happen on their own. We go deeper into the mechanics in a separate post on investing a lumpsum through STP.

If your money arrives every month, like salary, a SIP is the natural fit and there is nothing to decide. The lumpsum-or-spread question only comes up when a big amount is already in hand.

Before you invest a rupee of it

A windfall is the best chance most families get to fix things that monthly salary never quite covers. So go in this order:

1. Clear expensive debt. Credit card dues often cost 3–4% a month, which is 36–48% a year. No fund will beat that. A personal loan, which usually costs well into double digits, is also worth prepaying; the personal loan EMI calculator shows how much interest a part-payment saves.
2. Build a cash cushion. If losing your job tomorrow would mean borrowing for rent and EMIs within a couple of months, fill that gap first. An emergency fund sits in an FD or sweep-in account, not in equity.
3. Separate money with a date on it. If ₹2 lakh of this is for a car next year or a wedding in 2028, it does not belong in equity at all. Put it in an FD timed to the goal; the FD calculator will tell you what it grows to.
4. Only then decide how the long-term part goes in.

Also remember that a bonus is taxed as salary. Your employer deducts TDS before paying it, so what lands in your account is already post-tax. If a lot of TDS was cut, check on the income tax calculator whether the year's total tax matches, so March doesn't bring a surprise.

Why lumpsum usually wins: time in the market

Over long periods, markets have gone up more often than down, so money waiting on the sidelines usually misses some growth. That is the whole case for lumpsum.

The best-known study is Vanguard's. Across rolling 10-year periods in the US from 1926 to 2011, investing everything at once beat spreading it over 12 months about two times out of three, and the UK and Australia showed the same pattern. The average advantage was modest, around 2.3%. Stretch the spreading to 36 months and the lumpsum won even more often. Morningstar India has a short summary. There is no equally long Indian study, but the logic is the same here.

In rupees, at an assumed 12% a year, ₹5 lakh invested today becomes ₹15,52,924 in 10 years on the lumpsum calculator. Now take the extreme case: you park it in a liquid fund for a full year at 6% (₹5.3 lakh) and invest only then. Nine years at 12% gives ₹14,69,732. Waiting a year cost about ₹83,000. And waiting for "the crash" often doesn't stop at a year. Months turn into years while the money earns 2.5% in a savings account. If you are unsure, start an STP. That is a decision. Waiting is not. At 10%, the plain lumpsum gives ₹12,96,871, so do your own planning at the lower figure.

The catch: what one bad month does to a lumpsum

Averages hide the one thing people actually remember. If you put ₹5 lakh in and the market falls 20% the next month, your statement shows ₹4 lakh. That is ₹1 lakh gone, on paper, in four weeks. Equity values fell by a third or more within months in 2008 and again in March 2020, so this is not a made-up fear.

The loss may be temporary, but the reaction often isn't. Plenty of first-time investors see that red number, sell in panic, and go back to FDs for the next ten years. That one decision costs far more than the 2% average edge a lumpsum gives.

Spreading the money doesn't stop a fall. It means less of your money is exposed when it happens, and the later instalments buy cheaper. Vanguard's numbers show this side too: in falling markets, cost averaging lost less. Lumpsum gives the better expected result. Spreading gives a narrower range of outcomes and a smaller worst case.

₹5 lakh, four ways, in four kinds of market

Here is ₹5 lakh over 10 years, before tax. The only thing that changes between rows is what the market does in the first six months; after that, equity grows at an assumed 12% a year. Money waiting for an STP earns 6% in a liquid fund. We worked these out month by month in a simple model, and the first cell matches the lumpsum calculator exactly.

A few things stand out.

• In a steady market, the 12-month STP ends about ₹54,000 behind the lumpsum. That is the price of caution when nothing goes wrong. A 6-month STP costs about ₹25,000, and half-and-half about ₹13,000.
• If the market falls right after you invest, the lumpsum ends about ₹2.4 lakh behind the 6-month STP, because all of it took the hit while the STP bought most of its units after the fall.
• In a long, slow slide, the longer STP wins clearly, since it keeps buying all the way down.
• In a rally, the lumpsum ends about ₹2.6 lakh ahead of the 12-month STP. Nobody knows in advance which of these rows is coming.

Also look at the worst moment in year one. In the "falls 20%" case the lumpsum statement shows ₹4,00,000. With a 12-month STP, the lowest it goes is about ₹4,93,900. Same market, very different feeling.

These are made-up market paths to show the trade-off, not forecasts.

How an STP works, and what it costs

You invest the full amount in the source fund, pick the target equity fund from the same fund house (a plain diversified fund, not the new fund offer or sector fund the RM happens to be pushing that week), and choose the amount, frequency and start date. Most fund houses offer weekly, monthly or quarterly transfers, and the minimum period is usually six months to a year. HDFC Mutual Fund's explainer covers the types.

Where to park the money. A liquid fund is the usual choice. Its value barely moves, and the exit load is tiny and lasts only six days (0.007% on day one, nil from day seven). An arbitrage fund is the other option. It is taxed like an equity fund, which helps people in high slabs, but its returns have usually been close to liquid funds, sometimes a bit lower, and many charge an exit load if you leave within a few weeks. Check the scheme document either way.

Tax on each transfer. Every transfer is a sale of liquid fund units. For units bought from April 2023, the small gain on each sale is taxed at your slab rate, same as FD interest. On ₹5 lakh over 12 months at 6%, those gains add up to about ₹13,100. In the 30% slab, with cess, that is roughly ₹4,100 of tax. Over 6 months, about ₹6,000 of gains and ₹1,900 of tax. Small, but it goes in your ITR.

On the equity side, each transfer starts its own holding clock. Sell within 12 months and the gain is short-term, taxed at 20% (section 196 of the Income-tax Act, 2025). After that it is long-term, taxed at 12.5% on gains above ₹1.25 lakh a year (section 198). Add 4% cess. For a 10-year goal, this barely matters, but with a 12-month STP the last instalment turns long-term almost a year later than a lumpsum would.

Many equity funds also charge an exit load, often around 1% if you sell within a year. That only bites if you pull out early.

A practical middle path

For most salaried people, this is what works:

• Small amount compared to what you already have invested (say a ₹60,000 bonus when your funds are worth ₹8 lakh): invest it in one go. Timing ₹60,000 is not worth the effort.
• Big amount compared to your portfolio (₹5 lakh when you have ₹2 lakh in funds, or this is your first time): put a third to half in right away, and STP the rest over 6 months.
• You know you'd panic at a fall: a full 6–12 month STP. You give up a little return for a much smaller worst case, and that is a fair trade if it keeps you invested.
• Don't stretch it past 12 months. The longer the money waits, the more you give up in a normal market.

Once the STP is running, leave it alone. If the market falls in month three, the remaining instalments are doing exactly their job.

If you already have an asset mix you follow, say 60% equity and 40% FD and PPF, the bonus is a chance to rebalance. Put it wherever the mix has drifted short, rather than all into equity by default.

Your age and your goal change the answer

If you are young, the job is steady and the goal is 20-plus years away, a lumpsum or half-and-half is fine. You have all that time to sit through a bad start, and every year of compounding counts. At 12%, money doubles roughly every six years (the rule of 72 explains the shortcut), so ₹5 lakh left for 15 years is about ₹27.4 lakh on the calculator.

If this is your first time in equity, go with a 6–12 month STP. Getting through the first fall without selling matters more than the last ₹25,000 of return.

If you are close to retirement, or the money is a gratuity or PF payout, most of it shouldn't go to equity at all. For the equity portion, a 6–12 month STP makes sense. The gratuity calculator and the retirement calculator help you size what you actually need.

If you need the money within three years, neither. Use an FD or RD. If you're weighing that choice, our SIP vs FD comparison goes through it.

Two bonuses, worked through

Say Rohan is 26, three years into his first job, and his bonus lands as ₹2 lakh after TDS. He has ₹45,000 rolling on a credit card and nothing saved beyond this month's salary. He spends about ₹35,000 a month.

The card goes first. At 3.5% a month, that ₹45,000 costs him about ₹1,575 in interest every month it sits there, and no fund comes close to that. The remaining ₹1.55 lakh covers roughly four and a half months of his spending, so it goes into a sweep-in FD and stays there. That is the whole bonus. Nothing goes into a fund this year, and the lumpsum-or-STP question never comes up. When the bank RM calls about a "one-time premium" plan, the answer is no.

What Rohan can do for equity is start a SIP from salary, even ₹5,000 a month, and raise it each April. A step-up SIP often does more over 15 years than any one bonus; try it on the SIP calculator. Next year's bonus is the one that can go into the market.

Now say Meera is 36. Her bonus is ₹5 lakh after TDS. She has run SIPs for seven years, her funds are worth about ₹12 lakh, she kept the SIPs going through March 2020, and apart from the home loan she has no debt. Her cushion is already in place.

About ₹1 lakh of the bonus is for a car she wants to buy next year, so that goes into an FD timed to it. The other ₹4 lakh is for retirement, more than 20 years away. Against ₹12 lakh already in funds, it is a sizeable top-up but not her first rupee in equity, and she has already watched a crash without selling. On the averages, a lumpsum is the right call for her.

She still prefers half now and half over six months. The table above shows what that costs on ₹5 lakh in a steady market: about ₹13,000 over 10 years. She treats that as cheap insurance. ₹2 lakh goes into the flexi-cap fund her SIP already uses, and ₹2 lakh goes into the same fund house's liquid fund with a 6-month STP into it. She leaves the existing SIP alone, raises it with the April increment, and makes a note that the small liquid fund gains go into next year's ITR. If her equity share had already run well above what she wanted, the same ₹4 lakh would go to PPF or FDs instead, to bring the mix back.

Notice that in both cases the thing everyone argues about, lumpsum or STP, was the smallest decision. Debt, the cushion and money with a date on it decided most of it. Once those are sorted, a lumpsum is the better bet more often than not. The best plan, though, is the one you will still be following when the market has a bad month.

Written by the Gainly team for general information, not as investment or tax advice. Rates and rules change, so check the latest before you decide; tell us if something here is out of date. Contact