Reverse SIP Calculator (Systematic Withdrawal Plan)
Estimate how long your investment corpus can provide monthly income.
What Is the Reverse SIP Calculator (Systematic Withdrawal Plan)?
Reverse SIP (also called a Systematic Withdrawal Plan, or SWP) is the opposite of a SIP — instead of investing monthly, you withdraw a fixed amount every month from an existing corpus. It's commonly used to generate regular income during retirement, letting the remaining balance stay invested and continue earning returns even as you draw it down.
The core question this answers is simple but important: given a corpus size, a withdrawal amount, and an expected return, how long will the money actually last? The answer depends on a tug-of-war between two forces — the corpus growing from investment returns, and shrinking from your monthly withdrawal. Whichever force is stronger determines whether the corpus slowly depletes, stays roughly flat, or actually keeps growing despite the ongoing withdrawals.
If you're still in the accumulation phase and want to know how large a corpus you're on track to build before you start withdrawing, see the Retirement Calculator. To check whether a given corpus meets a widely cited sustainable-withdrawal benchmark, the Financial Freedom Calculator is a useful companion.
Reverse SIP Calculator (Systematic Withdrawal Plan) Formula
Each month, the remaining corpus earns returns and then the withdrawal is subtracted, repeated until the balance runs out:
Balance(month) = Balance(month − 1) × (1 + r) − Withdrawal
How Is the Reverse SIP Calculator (Systematic Withdrawal Plan) Calculated?
The calculator simulates your corpus month by month: it grows at the expected monthly rate, then the withdrawal is subtracted. As long as the growth exceeds the withdrawal, the corpus could theoretically last indefinitely; when withdrawals exceed growth, the balance steadily declines until it's depleted.
This month-by-month simulation is a more realistic model than simply dividing the corpus by the withdrawal amount, because it accounts for the fact that the remaining balance keeps compounding while you draw it down — which is exactly why a well-invested corpus can often sustain withdrawals for far longer than a naive "corpus ÷ withdrawal" calculation would suggest.
Reverse SIP Calculator (Systematic Withdrawal Plan) Example
A $5,000,000 corpus with $50,000/month withdrawals at 8% return lasts roughly 13.8 years (about 165 months) before depleting.
A smaller $2,000,000 corpus with $20,000/month withdrawals at 7% return lasts about 12.5 years (roughly 151 months) — a smaller corpus and a similar proportional withdrawal produce a somewhat shorter, but comparable, timeline.
A $10,000,000 corpus withdrawing $60,000/month at 9% return doesn't deplete at all within the projection — at that rate, the corpus earns roughly $75,000 in interest in the very first month alone, more than the withdrawal itself, so the balance actually keeps growing over time instead of shrinking.
How to Use the Reverse SIP Calculator (Systematic Withdrawal Plan)
Step 1
Enter your total investment corpus.
Step 2
Enter the monthly withdrawal amount you need.
Step 3
Enter the expected annual return on the remaining corpus.
Step 4
Click Calculate Duration to view how many months or years the corpus is projected to last.
Step 5
Try lowering the monthly withdrawal slightly to see how much longer the corpus would last.
Step 6
Compare a couple of different return assumptions, since actual investment returns are never perfectly steady.
Benefits
- Share your withdrawal timeline as a polished image card instead of just a link, useful when discussing a retirement drawdown plan with family.
- Shows whether your planned withdrawal rate is sustainable for your corpus.
- Useful for retirement income planning without depleting savings too early.
- Helps compare different withdrawal amounts against the same corpus.
- Models compounding on the remaining balance instead of a flawed simple-division estimate.
- Free, fast, and works entirely in your browser without any account.
Common Reverse SIP Calculator (Systematic Withdrawal Plan) Scenarios
Scenario 1
Planning a sustainable monthly retirement income from savings.
Scenario 2
Checking whether a target corpus can support a desired lifestyle.
Scenario 3
Comparing different withdrawal rates to extend how long funds last.
Scenario 4
Deciding how much of a windfall or lumpsum payout can safely be drawn down monthly.
Scenario 5
Testing whether a projected retirement corpus (from the Retirement calculator) will actually last through retirement.
Scenario 6
Comparing a self-managed systematic withdrawal against an insurance annuity quote.
Understanding Your Result
The duration shown is how long your corpus is projected to sustain the given monthly withdrawal at the assumed return rate. If withdrawals are lower than what the corpus earns on average, funds could last far longer than the calculator's 1000-month cap suggests, and in some cases — as in the third example above — the corpus may not deplete at all.
If the projected duration feels short relative to your expected retirement length, the fix is usually one of three levers: withdraw less each month, start with a larger corpus, or accept a higher-return (and typically higher-risk) allocation for the remaining balance — this calculator makes it easy to test how each of those changes the outcome.
Tips
- A withdrawal rate around 4% of the corpus annually is a commonly cited sustainable benchmark (see the Financial Freedom calculator).
- Consider a lower withdrawal rate than the maximum sustainable one to leave a buffer for market downturns.
- Revisit your withdrawal plan periodically as your corpus and expenses change.
- If your withdrawal rate is close to your expected return rate, small return shortfalls in bad years can deplete the corpus much faster than this steady-rate projection suggests.
- Consider keeping a portion of the corpus in lower-volatility assets specifically to fund near-term withdrawals, even if the rest stays invested for growth.
Common Mistakes
- Withdrawing more than the corpus's expected returns can sustain, depleting it faster than expected.
- Not accounting for inflation, which erodes the real value of a fixed monthly withdrawal over time.
- Assuming a constant return rate rather than the year-to-year variability of real markets.
- Withdrawing a fixed rupee amount without ever revisiting it, even as the corpus balance and personal expenses change substantially over the years.
- Not stress-testing the plan against a run of poor early returns, which can deplete a corpus much faster than an average-return projection implies.
Frequently Asked Questions
What happens if my withdrawal rate is too high?
If withdrawals exceed what the returns can sustain, the corpus depletes faster — reduce the monthly withdrawal or increase the corpus to extend the timeline.
Is this the same as a Systematic Withdrawal Plan (SWP)?
Yes, Reverse SIP and SWP describe the same strategy: withdrawing a fixed amount periodically from an invested corpus.
Does the corpus keep earning returns while I withdraw?
Yes, the remaining balance continues to earn the expected return each month, which helps the corpus last longer than a simple division would suggest.
Should my monthly withdrawal increase with inflation?
Many retirees increase withdrawals annually to keep pace with rising costs — this calculator uses a fixed withdrawal amount, so factor in a margin if you plan to increase it over time.
What withdrawal rate is considered sustainable?
A commonly cited sustainable range is 3-4% of the corpus annually, though the right rate depends on your expected returns, corpus size, and how long the withdrawals need to last.
Does inflation affect how long my corpus lasts?
Yes — if you don't increase withdrawals over time, inflation erodes their real value, but if you do increase them to keep pace with inflation, your corpus will typically run out faster than a flat-withdrawal scenario at the same starting rate.
Can I use Reverse SIP to plan retirement income?
Yes, it's commonly used to model how long a retirement corpus will last given a planned monthly withdrawal, or to find a sustainable withdrawal amount for a given corpus.
What happens if my withdrawal rate exceeds my investment return?
The corpus will shrink faster than it earns, similar to spending down savings — the calculator shows exactly when it would run out under those assumptions.
Is Reverse SIP the same as an annuity?
No — an annuity is an insurance product that guarantees income (often for life) in exchange for a lump sum, while a Reverse SIP simply withdraws from your own invested corpus, which isn't guaranteed to last if assumptions don't hold.
Can I share my Reverse SIP / SWP estimate as an image?
Yes — tap Share and, on supported devices, your estimate is shared as a branded image card, not just a text link.
Why does the calculator cap the estimate at 1000 months?
It's a practical safety limit — if a corpus with low withdrawals relative to returns hasn't depleted after roughly 83 years, it's effectively sustainable indefinitely under the assumed rate, so the simulation stops rather than looping unnecessarily.
Is it better to withdraw a fixed rupee amount or a fixed percentage of the corpus each month?
A fixed percentage automatically adjusts down if the corpus shrinks (extending its life) and up if it grows, while a fixed rupee amount — what this calculator models — is more predictable for budgeting but doesn't self-correct during a downturn.
Can I use this to figure out the maximum withdrawal my corpus can sustain?
Yes — try a few different monthly withdrawal amounts against the same corpus and return rate to see roughly where the duration starts dropping sharply, which points to the withdrawal level where sustainability turns risky.
Does market volatility matter even if the average return is high enough?
Yes — this calculator assumes a smooth, constant return, but real portfolios experience ups and downs; withdrawing a fixed amount during a market downturn early in retirement can deplete a corpus faster than the same average return spread evenly would suggest, a risk often called sequence-of-returns risk.
References
Important Information
This calculator provides estimates based on the expected return you enter. Actual investment returns vary with market performance.
Last updated: July 25, 2026