When a 20-Year Refinance Lowers the Payment and Raises the Interest

The quote is selling you the term, not the rate

This is the case the calculator flags in words rather than leaving to the numbers, because the numbers are arranged to be misread. The offer here is 6.5% against a current rate of 5.5%. It is a worse rate, plainly and on its face, and yet the monthly payment it produces is lower than the $760 you pay now. Nothing dishonest has happened. The new payment is smaller because the loan has been stretched over twenty years, and stretching any balance over more years lowers the monthly figure regardless of what the rate does. A quote that leads with the new monthly payment is inviting you to read a longer term as a discount.

It is not a discount. You pay interest on the outstanding balance for every month the loan exists, so adding years adds interest twice over: once because the rate itself is higher, and again because the higher rate is applied for longer to a balance that is now coming down more slowly. On these inputs the interest row above goes the wrong way, and the saving is reported as a negative number precisely so it cannot be skimmed past. The comparison the lender wants you to make is between two monthly payments. The comparison that decides whether you are better off is between two lifetime interest totals, and they point in opposite directions here.

None of which makes a longer term wrong. A lower required payment has genuine value when it is the difference between meeting your obligations comfortably and living one bad month away from a missed one, and buying that breathing room with additional interest can be a completely rational purchase. What is not rational is buying it without knowing the price, which is what happens when the quote is read as a rate improvement. If the reason you are considering this offer is that $760 is uncomfortably tight, then the honest framing is that you are buying insurance and the interest row is the premium. If the reason is that you think 6.5% is somehow better than 5.5%, the page has now told you otherwise.

There is a structure that gets you most of both. Refinance to the longer term so the required payment is low, then voluntarily keep paying close to the old, larger amount every month. The obligation is the smaller one in any month that goes badly; the actual payment is the larger one in every month that does not. Model that here by entering the refinance and putting the difference into the extra payment field. It only works if the new loan has no prepayment penalty — check that in the contract, not in the marketing.

How to price twenty years against ten before you sign

Use the term field on this page as the variable it really is. Leave the $68,000 balance and the 6.5% offer where they are and walk the term down from twenty years. The required monthly payment climbs steadily as you shorten it, and the lifetime interest falls the whole way. Somewhere on that walk the interest row crosses back over your current 5.5% schedule, and that crossing point is the real content of the offer: it is the shortest term at which this lender's rate stops costing you money. If the payment at that term is one you could actually meet every month, the offer is worth taking on those terms and not on the ones printed on the quote.

That reframes the negotiation, too. Lenders quote a term because it is the lever that makes the monthly number attractive, and terms are usually available in a range rather than as a single option. Asking for the same rate over a shorter term is an ordinary request, and it costs nothing to make. Ask for the figure in writing, then come back here and check it against the current schedule instead of against the twenty-year version you were shown first.

Two limits of this page are worth stating while you do that. It applies no origination or application fee to the refinance, so an offer that carries one is slightly better here than in life; add the fee to the balance before comparing if you want an honest figure. And it assumes a fixed rate throughout. A variable-rate offer will usually quote a starting rate below any fixed alternative, and that rate is not a promise — run the highest rate the contract permits, not the one on the marketing page, and see whether the comparison survives it.

When the minimum payment never gets you anywhere

If your minimum payment is at or below the interest accruing each month, the loan does not have a long payoff time. It has none. The balance grows every month you pay exactly as agreed, and it will keep growing for as long as that arrangement holds. This page reports that as its own outcome rather than as a very large number of months, because a month count in that situation is not an answer — it is whatever the calculator's iteration limit happened to be, dressed up as arithmetic. When you see it, the number you need is not a payoff date but the payment that would start reducing the balance at all, which is anything above the monthly interest: the balance multiplied by the annual rate, divided by twelve.

This situation is more common than it sounds, and it is not always a mistake. Some repayment arrangements deliberately set a payment below the accruing interest for a period, on the understanding that the shortfall is either subsidised or added to the balance later. Growing balances also show up during a graduated repayment period, during forbearance, and whenever a borrower is paying a fixed token amount while income recovers. What makes it dangerous is unpaid interest being capitalized — added to principal — at the end of such a period, because from that moment the interest starts earning interest, and the loan you owe is larger than the loan you borrowed. This calculator does not model any capitalization event; it assumes the balance you enter is the balance today and that no unpaid interest is ever rolled into it.

A second thing this calculator will not do is invent a payoff date for a schedule that technically amortizes but takes longer than a century. A payment one dollar above the monthly interest does eventually clear the loan, in the same sense that a dripping tap eventually fills a reservoir. Reporting that as a number of years would be technically true and practically worthless, so it is reported as its own outcome too. Between them, these two rules mean every figure this page shows you comes from a schedule that actually finishes.

A lower monthly payment is not a cheaper loan

The most common way a refinance quote misleads has nothing to do with the rate. It is the term. Stretching the same balance over more years lowers the monthly payment arithmetically, whatever happens to the rate, and a quote that leads with the new monthly figure is inviting you to read a longer term as a discount. It is not one: you pay interest for every year the loan exists, so more years at a lower rate can easily cost more in total than fewer years at a higher one. This page flags that case explicitly rather than letting the monthly figure carry the argument, and the interest row will show a negative saving when it happens.

That does not make a longer term wrong. A lower required payment has real value if it is the difference between meeting your obligations comfortably and living one bad month away from a missed payment, and buying that breathing room with additional interest can be an entirely rational purchase. The point is to know the price. Refinancing to a longer term and then voluntarily paying the old, higher amount each month gets you both the lower obligation and the shorter payoff, which is often the best available structure — run that case here by entering the refinance and putting the difference in the extra payment field.

Two things this calculator does not include are worth naming. It applies no origination or application fee to the refinance, so a quote that carries one is slightly better on this page than in life; add any such fee to the balance before comparing if you want the honest figure. And it assumes a fixed rate throughout. A variable-rate refinance offer will usually quote a starting rate below any fixed alternative, and that rate is not a promise — modelling it as fixed here would understate its cost in any environment where rates rise. If the offer in front of you is variable, run this page at the highest rate the contract permits, not the one on the marketing page, and see whether the comparison still favours it.