Got ₹5 Lakh sitting in your savings? Should you invest it all at once (lump sum) or spread it over months via SIP? The internet says "SIP is always safer." The data tells a different story.
The truth: it depends on market conditions
Neither lump sum nor SIP is universally better. What matters is the overall market environment when you're deploying. PE is one indicator, but volatility, momentum, and trend structure all play a role.
That's why SIPshift uses a multi-factor Shift Score instead of relying on PE alone. The score already accounts for whether conditions genuinely favor deploying more or holding back:
| Shift Score | Better approach | Why |
|---|---|---|
| 80+ (Rare opportunity) | Lump sum | Multiple signals confirm attractive conditions. Deploy quickly to capture the opportunity. |
| 60-79 (Attractive) | Split over 2-3 months | Conditions are favorable but not extreme. Spreading gives a good average. |
| 35-59 (Average) | Spread over 4-6 months | No strong signal either way. Gradual deployment reduces timing risk. |
| Below 35 (Below average) | Keep in FD or debt funds (~7% return) | Conditions historically unfavorable. Wait for the score to improve. |
What the data shows (13 years)
We tested both approaches across every possible starting month from 2012-2025:
• When Shift Score was 70+: Lump sum beat SIP 78% of the time over 12 months
• When Shift Score was below 35: SIP beat lump sum 65% of the time
• At average scores (35-59): Both performed similarly, within 1-2% of each other
The key insight: Lump sum wins when conditions are genuinely attractive (not just cheap PE). SIP wins when conditions are unfavorable. The question isn't "which is better" but "what does the Shift Score say?"
Even a high score can't predict black swan events.
Markets can crash at any score due to unpredictable events like wars, pandemics, or global financial crises. No model has a crystal ball. The Shift Score tells you what historical conditions suggest, not what the future guarantees. This is exactly why we never recommend deploying 100% at once, even at score 80+.
How SIPshift helps you decide
Instead of guessing, check the Shift Score:
• Score 80+: Rare opportunity. Deploy 40-50% of surplus cash
• Score 70-79: Very attractive. Deploy 20-25% of surplus cash
• Score 60-69: Attractive. Deploy 10-15% of surplus cash
• Score 35-59: Average. Deploy 5-10% of surplus cash
• Score below 35: Keep in FD or debt funds (~7% return), check again next month
This removes the "lump sum vs SIP" debate entirely. You deploy based on data, not gut feel. Some months you put more, some less. Over time, your average cost ends up lower than either pure lump sum or pure SIP.
What about tax efficiency?
If your lump sum comes from:
• Bonus/salary: No tax concern, deploy per score
• Selling existing investments: Check if you'll trigger LTCG. If so, spread deployment to stay under ₹1.25L annual exemption
• RSU vesting: Already taxed at vesting. Deploy per score.
The bottom line
Stop asking "lump sum or SIP." Start asking "what does the market favor right now?" Check the Shift Score, deploy accordingly, and let the data guide your pace.