Student Loan Payoff vs Invest Calculator

This calculator helps you decide whether to make a voluntary lump-sum repayment on your New Zealand student loan or invest the money instead, a question with a clearer answer here than almost anywhere else in the world. The reason is that New Zealand student loans are interest-free for borrowers who are based in New Zealand. Because the loan does not grow, repaying it early saves you no interest; you still make the same compulsory repayments through your pay, just for a slightly shorter time. Investing the same lump sum, on the other hand, can grow it through compound returns. For a New Zealand-based borrower, that usually makes investing the mathematically stronger choice in pure dollar terms, though paying off the loan has real psychological value and matters if you are about to move overseas, because loans become interest-bearing for borrowers living abroad. This tool makes the comparison concrete. You enter the lump sum you have available, an expected investment return, the number of years to look ahead, and the loan interest rate, which is zero for a New Zealand resident but can be set higher if you are, or will be, overseas. The calculator shows what the lump sum could grow to if invested, the interest you would save by repaying, and which option comes out ahead. Use it to make an informed call rather than repaying on autopilot. Remember the wider picture: investments carry risk and can fall, an emergency fund and high-interest debt should usually come first, and the certainty of being debt-free has value the numbers do not capture. This is an estimate to guide the decision, not financial advice.

NZ-based student loans are interest-free, so repaying early saves no interest. Loans become interest-bearing if you move overseas. Not advice.