Opportunity Cost
The value of the next-best alternative you give up when you commit money to one choice. For example, prepaying a loan at 8.5% instead of investing the same amount at an expected higher return.
Mathematical Formula
Context & Practical Application
What is Opportunity Cost? (Simple Terms)
Opportunity cost is what the money spent on one choice could have earned in its next-best use. Every prepayment carries one: the same rupees could have gone into an investment instead.
Prepaying a ₹50 Lakhs home loan at 8.5% locks in a guaranteed 8.5% saving; an equity fund might return about 12%, but with market risk.
Understanding Opportunity Cost
The comparison follows a break-even rule: prepaying earns a guaranteed return equal to the loan rate, while investing earns an uncertain, post-tax return. When the expected investment return is clearly above the loan rate, investing has the higher expected payoff; below it, prepayment wins.
This frame drives the prepay-versus-invest decision, including whether to route the money into a SIP. Work through it in Loan Prepayment vs Investing, and compare growth rates using CAGR.
Mathematical Analysis of Opportunity Cost
The net advantage of investing the extra amount rather than prepaying is approximately:
The expression is linear in the extra amount but ignores timing: prepayment frees cash flows early, while investment outcomes arrive later, so a full comparison must match cash flows period by period. Edge case: when the expected return equals the loan rate, the two paths are equivalent before tax, and any prepayment penalty tilts the balance toward investing.
Referenced In Guides & Comparisons
Learn how Opportunity Cost is applied in real-world scenarios across our pathways: