What is an SWP Calculator?
An SWP Calculator (Systematic Withdrawal Plan Calculator) helps investors and retirees plan regular monthly cash payouts from their mutual fund investments while monitoring remaining principal sustainability.
SWP is widely regarded by certified financial planners (CFPs) as the single most tax-efficient method to generate regular monthly income or post-retirement pension cash flow.
How SWP Math Works
Each month, a fixed cash payout ($W$) is withdrawn from the current corpus balance ($B_m$). The remaining balance compounds at monthly interest rate $i = \frac{\text{Annual Rate}}{12 \times 100}$:
$$B_m = (B_{m-1} \times (1 + i)) - W$$
Where:
- $B_{m-1}$: Opening corpus balance at month $m-1$.
- $i$: Monthly return rate decimal.
- $W$: Monthly cash withdrawal payout.
Practical Worked Example: ₹50 Lakh Retirement Corpus
Suppose a retiree invests a lump-sum corpus of ₹50,00,000 (₹50 Lakhs) in a conservative hybrid mutual fund earning 8% p.a. and sets up a monthly SWP of ₹30,000 for 10 years:
- Initial Corpus: ₹50,00,000
- Monthly Payout: ₹30,000 (₹3,60,000 per year)
- Total Cash Withdrawn over 10 Years: $₹30,00,000 \times 120 = \mathbf{₹36,00,000}$
- Remaining Corpus Balance after 10 Years: ₹44,87,356
Despite withdrawing ₹36 Lakhs in monthly income, the remaining portfolio balance stands strong at ₹44.87 Lakhs because monthly compounding growth continuously offsets payouts!
SWP vs. Bank Fixed Deposit (FD) Monthly Interest
| Feature | Bank FD Monthly Interest | Mutual Fund SWP |
|---|---|---|
| Taxation | 100% of interest taxed as per income tax slab (up to 30%+ cess). | Only profit portion of redeemed units taxed (12.5% LTCG). |
| Capital Growth | Principal remains fixed (eroded by inflation). | Remaining units continue compounding & growing. |
| Flexibility | Fixed interest rate for tenure. | Change withdrawal amount or stop SWP anytime. |
| TDS Deduction | 10% TDS deducted automatically by banks. | No TDS deducted on domestic resident redemptions. |