Refinancing Your Mortgage: Running the Numbers

The basic test is break-even: divide total closing costs by the monthly saving to get the number of months before you are ahead. Spend $6,000 to save $250 a month and you break even at 24 months. Stay longer and you profit; sell sooner and you lost money.

The term reset that quietly erases the saving

Here is where the simple calculation misleads. If you are eight years into a 30-year mortgage and refinance into a new 30-year, you have added eight years of payments. The monthly figure falls, partly from the better rate and partly from stretching the remaining balance over a longer period.

Total interest can rise even at a lower rate. To compare honestly, either refinance into a term matching your remaining years — a 22-year, or a 20-year if that is what is offered — or compare total remaining interest on both loans rather than monthly payments.

Amortisation makes this worse than intuition suggests. Early payments are mostly interest; later payments are mostly principal. Resetting to year one of a new schedule returns you to the interest-heavy portion of the curve.

What closing costs actually consist of

Expect roughly 2 to 5 percent of the loan amount: origination or underwriting fees, appraisal, title search and title insurance, recording fees, credit report, and prepaid items like escrow deposits.

Ask for a Loan Estimate from each lender. It is a standardised federal form, which makes side-by-side comparison genuinely possible — one of the more useful pieces of consumer protection in US mortgage lending. Compare the total closing costs figure, not the rate alone.

No-closing-cost refinances are not free

These come in two forms. Either the costs are rolled into the loan balance, so you borrow more and pay interest on the fees for decades, or you accept a higher rate in exchange for the lender covering them — a lender credit.

The higher-rate version can be sensible if your horizon is short, since you avoid upfront cost and the rate premium only applies while you hold the loan. Rolling costs into the balance is usually the worse option, because you pay interest on the fees for the whole term.

Cash-out refinancing

Cash-out replaces your mortgage with a larger one and pays you the difference. Rates are typically slightly higher than rate-and-term refinances, and most lenders require you to retain at least 20 percent equity.

The uses that make sense are ones that improve your position: home improvements that add value, or consolidating genuinely high-rate debt at a much lower rate. The risk is the same as any secured consolidation — unsecured debt becomes debt secured against your home, over 30 years. Consolidating $30,000 of card debt into a mortgage can mean paying for it until retirement.

PMI and appraisals

If you are paying private mortgage insurance and your equity has grown past 20 percent, you may not need a refinance at all. Conventional loans generally allow PMI removal on request at 80 percent loan-to-value, and it terminates automatically at 78 percent. An appraisal costs a few hundred dollars against potentially thousands of PMI premiums.

FHA loans are different: mortgage insurance premiums often persist for the life of the loan, which makes refinancing into a conventional mortgage the standard route to shedding them once equity allows. That is frequently a stronger reason to refinance than the rate itself.

A sensible checklist

Establish how long you realistically expect to keep the house. Get Loan Estimates from at least three lenders within a two-week window so the credit enquiries consolidate. Compare total closing costs and total remaining interest, not monthly payments. Match the new term to your remaining years unless you have a deliberate reason not to.