Top-up personal loan: what the fresh tenure costs you

A top-up comes in two forms and the offer rarely says which one you are getting.

The first is a true add-on: the extra amount is disbursed as a separate tranche with its own tenure, and the original loan keeps its schedule. This is uncommon for personal loans. The second, and the one most people receive, is a merge: the lender forecloses the existing loan, adds the new amount to the outstanding balance, and books one new loan for the total, usually over a fresh full tenure. One loan, one EMI, one end date, and the end date is later than the one you had.

The alternative is a second, fresh loan. The old loan is left alone and finishes on schedule. The new money is a separate loan at whatever rate and tenure you can get for it. Two EMIs for a while, then one, then none.

A top-up is a lender's favourite kind of loan. It has watched 24 EMIs clear from your account, so the credit decision is mostly done. No acquisition cost, no fresh KYC, no marketing spend to win you, and the exposure grows on a borrower it already understands. None of that makes the loan cheap for you; it makes the lender want to write it.

The other reason is arithmetic. Every lender runs your combined EMI against your income before sanctioning, and a 60-month merge produces a smaller EMI than any other way of raising the same money. On a ₹50,000 income at a 50 percent cap, here is how the routes land.

The existing loan: ₹5 lakh at an illustrative 14 percent over 60 months, EMI ₹11,634. After 24 EMIs you have paid ₹1,19,621 in interest, the balance is ₹3,40,402, and the remaining 36 EMIs would cost ₹78,427 more. Now you need ₹2 lakh, and the lender offers ₹5,40,402 merged at the same 14 percent over a fresh 60 months: EMI ₹12,574, total interest ₹2,14,050. Here is that ₹2,14,050 split by what each rupee of principal is doing.

A top-up beats a fresh loan under one condition, and it is not the rate. It is that the merged tenure is short enough that the old balance is not stretched, or only a little. The rate helps only once that is true.

Take the same ₹5,40,402 merged at 14 percent but over 36 months, the tenure the old loan had left anyway. EMI ₹18,470, total interest ₹1,24,506. Against keeping the old loan and adding a fresh ₹2 lakh at an illustrative 16 percent over 36 months, combined EMI ₹18,666 and combined remaining interest ₹1,31,557, the 36-month merge wins on both counts, by ₹196 a month and ₹7,052 in interest. The old balance is not reset and the new money is two points cheaper.

This is the version most people sign, because it has the smallest EMI on the page. Merged ₹5,40,402 at 14 percent over 60 months: ₹12,574 a month against ₹21,427 for the old loan plus a 24-month fresh loan at 16 percent. The monthly gap is ₹8,853, and that is the entire sales case. It is real: for two years the merge is genuinely lighter on the account.

The interest gap runs the other way. ₹2,14,050 against ₹1,13,450: the merge costs ₹1,00,600 more, and a higher rate on the fresh loan does not close that gap. Even a fresh ₹2 lakh at 18 percent over 24 months, four points above the existing loan, leaves the combined route ₹95,988 cheaper. The extra lakh buys 24 more months on money you had already paid two years of interest on, plus 36 extra months on the new money.

The offer leads with the rate and the EMI. Neither decides whether it is a good deal. These do.