ToolsSIP check
Does the amount you put in matter more than the return?
For the corpus, yes. Raising a Nifty 500 SIP 15% a year left its ten-year return almost where it was (12.9% against 12.8%) but grew the median corpus from Rs 23.3 lakh to Rs 41.6 lakh, because more money went in. Starting ten years late, matching a 20-year SIP's median corpus took about ₹47,733 a month instead of Rs 10,000. And a 1% a year higher cost, the usual gap between a regular and a direct plan of an active fund, took 8.7% off a 15-year corpus.
Written for SIP investors deciding how much to put in, and through which plan. Data to 6 Oct 2026.
Step-ups
A step-up raises the instalment once a year by a fixed share: Rs 10,000 a month in the first year, Rs 11,500 in the second at 15%, and so on. XIRR measures the return on each rupee, so it barely moves; what changes is how many rupees are working. The bars set the money put in against the median final value across start months, after tax.
Ten years of a Nifty 500 SIP, with and without a step-up
Money put in and the median final value after tax, Rs lakh, start months from Apr 2005
How to read it. The gap between the two bars is what the market added. With no step-up, Rs 12.0 lakh became Rs 23.3 lakh at the median; with a 15% step-up, Rs 24.4 lakh became Rs 41.6 lakh. Over fifteen years the 15% step-up turned Rs 57.1 lakh into Rs 121.6 lakh, against Rs 51.1 lakh without it, though fifteen-year windows here add up to only one independent period.
Ten years of a Nifty 500 SIP, with and without a step-up. Bar chart of 4 items. Money put in: highest 15% more each year at 24.4, lowest No step-up at 12.0.
Median across start months. 'Today's rupees' deflates the final value by CPI to the latest month. XIRR is after tax.
| Portfolio | Years | Step-up | Put in | Final value, median | In today's rupees | XIRR, median | Windows | More |
|---|---|---|---|---|---|---|---|---|
| Nifty 50 | 5 | No step-up | ₹6,00,000 | ₹8,15,972 | ₹12,01,747 | 12.2% | 199 | |
| Nifty 50 | 5 | 5% more each year | ₹6,63,076 | ₹8,91,060 | ₹13,12,721 | 12.2% | 199 | |
| Nifty 50 | 5 | 10% more each year | ₹7,32,612 | ₹9,72,728 | ₹14,34,442 | 12.1% | 199 | |
| Nifty 50 | 5 | 15% more each year | ₹8,09,086 | ₹10,62,596 | ₹15,69,402 | 12.1% | 199 | |
| Nifty 50 | 10 | No step-up | ₹12,00,000 | ₹22,37,145 | ₹29,19,763 | 12.0% | 139 | |
| Nifty 50 | 10 | 5% more each year | ₹15,09,347 | ₹26,94,681 | ₹35,08,264 | 12.0% | 139 | |
| Nifty 50 | 10 | 10% more each year | ₹19,12,491 | ₹32,75,088 | ₹42,85,237 | 12.0% | 139 | |
| Nifty 50 | 10 | 15% more each year | ₹24,36,446 | ₹40,15,719 | ₹52,80,338 | 12.1% | 139 | |
| Nifty 50 | 15 | No step-up | ₹18,00,000 | ₹47,42,771 | ₹54,16,943 | 12.0% | 79 | |
| Nifty 50 | 15 | 5% more each year | ₹25,89,428 | ₹62,16,782 | ₹70,75,744 | 12.0% | 79 | |
| Nifty 50 | 15 | 10% more each year | ₹38,12,698 | ₹84,09,226 | ₹95,00,429 | 12.2% | 79 | |
| Nifty 50 | 15 | 15% more each year | ₹57,09,649 | ₹1,16,01,042 | ₹1,30,35,627 | 12.4% | 79 | |
| Nifty 500 | 5 | No step-up | ₹6,00,000 | ₹8,40,520 | ₹12,41,823 | 13.4% | 199 | |
| Nifty 500 | 5 | 5% more each year | ₹6,63,076 | ₹9,17,287 | ₹13,52,409 | 13.4% | 199 | |
| Nifty 500 | 5 | 10% more each year | ₹7,32,612 | ₹10,02,732 | ₹14,73,564 | 13.5% | 199 | |
| Nifty 500 | 5 | 15% more each year | ₹8,09,086 | ₹10,96,398 | ₹16,06,025 | 13.5% | 199 | |
| Nifty 500 | 10 | No step-up | ₹12,00,000 | ₹23,33,217 | ₹30,38,772 | 12.8% | 139 | |
| Nifty 500 | 10 | 5% more each year | ₹15,09,347 | ₹27,99,188 | ₹36,52,234 | 12.8% | 139 | |
| Nifty 500 | 10 | 10% more each year | ₹19,12,491 | ₹33,95,562 | ₹44,23,962 | 12.8% | 139 | |
| Nifty 500 | 10 | 15% more each year | ₹24,36,446 | ₹41,61,218 | ₹54,09,459 | 12.9% | 139 | |
| Nifty 500 | 15 | No step-up | ₹18,00,000 | ₹51,14,305 | ₹58,31,901 | 12.8% | 79 | |
| Nifty 500 | 15 | 5% more each year | ₹25,89,428 | ₹66,60,474 | ₹75,59,183 | 12.9% | 79 | |
| Nifty 500 | 15 | 10% more each year | ₹38,12,698 | ₹88,30,590 | ₹1,00,67,891 | 12.9% | 79 | |
| Nifty 500 | 15 | 15% more each year | ₹57,09,649 | ₹1,21,55,293 | ₹1,38,18,315 | 13.1% | 79 | |
| Nifty Smallcap 250 | 5 | No step-up | ₹6,00,000 | ₹9,10,213 | ₹12,74,982 | 16.7% | 199 | |
| Nifty Smallcap 250 | 5 | 5% more each year | ₹6,63,076 | ₹9,94,920 | ₹13,98,603 | 16.8% | 199 | |
| Nifty Smallcap 250 | 5 | 10% more each year | ₹7,32,612 | ₹10,85,467 | ₹15,32,172 | 16.9% | 199 | |
| Nifty Smallcap 250 | 5 | 15% more each year | ₹8,09,086 | ₹11,83,316 | ₹16,74,734 | 17.0% | 199 | |
| Nifty Smallcap 250 | 10 | No step-up | ₹12,00,000 | ₹25,58,901 | ₹32,25,320 | 14.5% | 139 | |
| Nifty Smallcap 250 | 10 | 5% more each year | ₹15,09,347 | ₹30,99,426 | ₹38,70,660 | 14.8% | 139 | |
| Nifty Smallcap 250 | 10 | 10% more each year | ₹19,12,491 | ₹37,47,005 | ₹46,60,781 | 14.9% | 139 | |
| Nifty Smallcap 250 | 10 | 15% more each year | ₹24,36,446 | ₹45,62,797 | ₹56,59,011 | 15.0% | 139 | |
| Nifty Smallcap 250 | 15 | No step-up | ₹18,00,000 | ₹56,40,334 | ₹64,06,947 | 14.0% | 79 | |
| Nifty Smallcap 250 | 15 | 5% more each year | ₹25,89,428 | ₹74,31,293 | ₹83,71,951 | 14.3% | 79 | |
| Nifty Smallcap 250 | 15 | 10% more each year | ₹38,12,698 | ₹1,00,77,914 | ₹1,10,87,670 | 14.7% | 79 | |
| Nifty Smallcap 250 | 15 | 15% more each year | ₹57,09,649 | ₹1,35,56,726 | ₹1,50,35,807 | 14.8% | 79 | |
| 60/40 | 5 | No step-up | ₹6,00,000 | ₹7,94,894 | ₹11,90,223 | 11.2% | 199 | |
| 60/40 | 5 | 5% more each year | ₹6,63,076 | ₹8,68,206 | ₹12,98,923 | 11.1% | 199 | |
| 60/40 | 5 | 10% more each year | ₹7,32,612 | ₹9,49,300 | ₹14,18,165 | 11.1% | 199 | |
| 60/40 | 5 | 15% more each year | ₹8,09,086 | ₹10,38,277 | ₹15,48,816 | 11.1% | 199 | |
| 60/40 | 10 | No step-up | ₹12,00,000 | ₹21,16,725 | ₹27,54,282 | 10.9% | 139 | |
| 60/40 | 10 | 5% more each year | ₹15,09,347 | ₹25,53,421 | ₹33,30,754 | 10.9% | 139 | |
| 60/40 | 10 | 10% more each year | ₹19,12,491 | ₹31,09,846 | ₹40,64,121 | 10.9% | 139 | |
| 60/40 | 10 | 15% more each year | ₹24,36,446 | ₹38,18,004 | ₹49,97,024 | 10.9% | 139 | |
| 60/40 | 15 | No step-up | ₹18,00,000 | ₹43,11,139 | ₹48,87,058 | 10.8% | 79 | |
| 60/40 | 15 | 5% more each year | ₹25,89,428 | ₹56,63,176 | ₹64,16,938 | 10.8% | 79 | |
| 60/40 | 15 | 10% more each year | ₹38,12,698 | ₹76,55,448 | ₹86,67,046 | 10.9% | 79 | |
| 60/40 | 15 | 15% more each year | ₹57,09,649 | ₹1,06,15,387 | ₹1,20,05,584 | 11.0% | 79 | |
| 60/20/20 | 5 | No step-up | ₹6,00,000 | ₹7,99,690 | ₹11,64,342 | 11.4% | 199 | |
| 60/20/20 | 5 | 5% more each year | ₹6,63,076 | ₹8,74,368 | ₹12,72,633 | 11.4% | 199 | |
| 60/20/20 | 5 | 10% more each year | ₹7,32,612 | ₹9,58,048 | ₹13,91,449 | 11.5% | 199 | |
| 60/20/20 | 5 | 15% more each year | ₹8,09,086 | ₹10,46,605 | ₹15,21,545 | 11.4% | 199 | |
| 60/20/20 | 10 | No step-up | ₹12,00,000 | ₹21,37,621 | ₹26,95,532 | 11.1% | 139 | |
| 60/20/20 | 10 | 5% more each year | ₹15,09,347 | ₹25,79,264 | ₹32,66,007 | 11.1% | 139 | |
| 60/20/20 | 10 | 10% more each year | ₹19,12,491 | ₹31,46,588 | ₹39,95,110 | 11.2% | 139 | |
| 60/20/20 | 10 | 15% more each year | ₹24,36,446 | ₹38,78,575 | ₹49,26,163 | 11.3% | 139 | |
| 60/20/20 | 15 | No step-up | ₹18,00,000 | ₹45,30,033 | ₹51,69,004 | 11.4% | 79 | |
| 60/20/20 | 15 | 5% more each year | ₹25,89,428 | ₹59,56,835 | ₹67,91,055 | 11.5% | 79 | |
| 60/20/20 | 15 | 10% more each year | ₹38,12,698 | ₹80,47,403 | ₹91,56,307 | 11.6% | 79 | |
| 60/20/20 | 15 | 15% more each year | ₹57,09,649 | ₹1,11,41,602 | ₹1,26,40,231 | 11.7% | 79 |
Starting late
The Nifty 500 total-return index goes back to 1995, so here the longest-history view is used: every start month from 1995 that leaves a full window. A 20-year SIP is set against one started five or ten years later that stops on the same date, so it runs 15 or 10 years, with the same Rs 10,000 a month. Twenty-year windows from 1995 add up to a single independent period, so read these as one history's arithmetic rather than odds.
The same instalment, started now or later
Nifty 500, Rs 10,000 a month: money put in and the median final value after tax, Rs lakh
How to read it. Twenty years turned Rs 24.0 lakh into Rs 117.6 lakh at the median. Starting five years later left Rs 56.5 lakh; ten years later, Rs 24.6 lakh. The last years of a long SIP add the most, because the whole pile is compounding.
The same instalment, started now or later. Bar chart of 3 items. Money put in: highest Start now, 20 years at 24.0, lowest Ten years late, 10 years at 12.0.
What a late start must put in to catch up
Monthly instalment needed to reach the median 20-year corpus, Nifty 500
How to read it. To match the median 20-year corpus, a SIP started five years late needed about ₹20,799 a month, and one started ten years late about ₹47,733: 2.1 and 4.8 times the instalment.
What a late start must put in to catch up. Bar chart of 3 items. Monthly instalment needed: highest Ten years late, 10 years at 47,733, lowest Start now, 20 years at 10,000.
Direct and regular plans
A regular plan pays the distributor out of the fund every year, so its expense ratio is higher than the direct plan's. The gap is around 0.5% a year for many index and debt funds and closer to 1% for active equity funds. Here the Nifty 500 SIP is run again with that extra cost taken out every day, against the direct-plan costs used everywhere else in the lab.
What a higher annual cost takes from the corpus
Nifty 500 SIP: median shortfall in final value against the direct plan, after tax
How to read it. An extra 1% a year left a 15-year SIP 8.7% smaller at the median and a 20-year one 11.9% smaller; an extra 0.5% cost 4.5% at fifteen years. Unlike the timing questions, this one is near certain: the cost is charged every day, in every market.
What a higher annual cost takes from the corpus. Bar chart of 4 items. 0.5% a year more: highest 20 years at 6.2%, lowest 5 years at 1.3%.
Nifty 500 SIP, median across start months from Apr 2005. Twenty-year windows: only those started by late 2006.
| Years | Plan | Final value, median | XIRR, median | Smaller than direct | Windows | More |
|---|---|---|---|---|---|---|
| 5 | Direct plan | ₹8,40,520 | 13.4% | 0.0% | 199 | |
| 5 | 0.5% a year more | ₹8,30,015 | 12.9% | 1.3% | 199 | |
| 5 | 1% a year more | ₹8,19,789 | 12.4% | 2.7% | 199 | |
| 10 | Direct plan | ₹23,33,217 | 12.8% | 0.0% | 139 | |
| 10 | 0.5% a year more | ₹22,68,280 | 12.2% | 2.8% | 139 | |
| 10 | 1% a year more | ₹22,05,641 | 11.7% | 5.5% | 139 | |
| 15 | Direct plan | ₹51,14,305 | 12.8% | 0.0% | 79 | |
| 15 | 0.5% a year more | ₹48,89,115 | 12.3% | 4.5% | 79 | |
| 15 | 1% a year more | ₹46,75,822 | 11.8% | 8.7% | 79 | |
| 20 | Direct plan | ₹96,27,153 | 12.4% | 0.0% | 19 | |
| 20 | 0.5% a year more | ₹90,27,332 | 11.8% | 6.2% | 19 | |
| 20 | 1% a year more | ₹84,71,025 | 11.3% | 11.9% | 19 |
What I predicted
Written into the specification on 8 October 2026, before any of these numbers existed.
S9 Held
Between no step-up and a 15% step-up, the median 10-year Nifty 500 XIRR changes by less than 0.5 point, while the median final value rises by more than 50%.
The median XIRR moved +0.16 pts, from 12.8% to 12.9%. The median final value rose 78%, from Rs 23.3 lakh to Rs 41.6 lakh, on Rs 24.4 lakh put in instead of Rs 12.0 lakh.
S12 Held
An extra 1% a year of running cost leaves a 15-year Nifty 500 SIP with a median final value 8% to 12% lower.
8.7% lower at the median, across 79 fifteen-year windows. Costs compound like returns do, so the loss keeps growing: 11.9% at twenty years.
Historical research on index portfolios, not investment advice. Returns are after fund costs; 'after tax' applies Indian capital-gains rules by date for a 30% slab investor and sells everything at the end. Most factor, mid-cap and small-cap index history before each index's launch date is back-tested by NSE. One 21-year sample, domestic assets only.
The workings
Data
Every chart has a table view, a CSV download and a link to its published JSON. Bundles are listed in data status.