Why You Should Prepay High-Interest Debt Before Investing

The Maths Is Simple

A personal loan at 15–18% interest is a guaranteed 15–18% loss every year. No mutual fund can reliably deliver that return — equity funds average 12–14% CAGR over the long run, and that is not guaranteed. Prepaying a 16% loan is the equivalent of earning a risk-free 16% return. Nothing in the market gives you that.

Once you factor in taxes on your investment gains, the gap widens further. Mutual fund gains above ₹1.25 lakh per year attract 12.5% LTCG tax. Your loan interest gives you no such relief (unless it is a home loan eligible for Section 24 deduction).

Which Loans to Prepay First

1. 1.Credit Card Outstanding (36–42%) — Highest priority. Carrying any balance forward costs 36–42% per year — clear it this month before anything else.
2. 2.Personal Loans (15–24%) — No tax benefit, unsecured, brutal compounding. Attack immediately after clearing credit card dues.
3. 3.Car Loans (9–12%) — Depreciating asset + interest. Prepay after clearing personal loans.
4. 4.Education Loans (8–12%) — Section 80E deduction applies for up to 8 years — factor this in before deciding.
5. 5.Home Loans (8–9%) — Lowest priority. Section 24 deduction up to ₹2L per year reduces your effective rate. Invest alongside instead.

The Practical Rule

If your loan interest rate is above 10%, direct at least 50% of your investable surplus toward prepayment. Keep a small Emergency Fund first (3 months of expenses), then attack the debt. Once EMI burden drops below 20% of your income, you can shift the full surplus into SIPs.

The fastest path to wealth is not the highest return — it is eliminating the guaranteed losses first.