15-year or 30-year? How to show the tradeoff so the client picks with open eyes

Short answer: the 15-year loan saves the client a large pile of interest and builds equity fast, but the payment is much higher and the cash is locked into the house. The 30-year keeps the payment low and leaves room to invest or build reserves, at the cost of more total interest. The right pick is not about which number is bigger. It is about what the client needs their money to do. Here is how to put both in front of them honestly.

What does the client actually give up with each?

The 15-year is a forced savings plan with a high minimum. The payment is steep because the loan is crushed in half the time, but almost every dollar goes to building equity, and the total interest is a fraction of the long loan.

The 30-year is the flexible choice. The payment is much lower, which frees up cash for retirement accounts, an emergency fund, or just breathing room. The cost is more interest paid over time, and slower equity early on.

Neither is virtuous or foolish. They are two different uses of the same dollar.

How big is the gap, really?

Put real numbers on it. A $400,000 loan, 15-year at 6.0 percent versus 30-year at 6.75 percent.

	15-year	30-year
Rate	6.0%	6.75%
Monthly principal and interest	about $3,375	about $2,595
Total interest over the loan	about $207,000	about $534,000
Equity after 5 years	about $110,000	about $34,000

The 15-year saves the client more than $325,000 in interest and builds equity three times faster. That is a real argument. But it costs $780 more every month, and that $780 is gone whether the client has a good year or a hard one.

So which one should the client take?

Walk them through three questions, not a sales pitch.

Can they carry the higher payment without going tight on cash? If the 15-year payment leaves them with no reserves, the 30-year is safer even though it costs more interest. An empty savings account is a bigger risk than extra interest.

Would the freed-up cash work harder elsewhere? A client who would actually invest the $780 difference each month, in a retirement match or a brokerage account, can sometimes come out ahead with the 30-year. A client who would just spend it usually does better being forced to save by the 15-year.

Do they value the payoff date or the flexibility? Some clients want the house free and clear in 15 years and will gladly pay for it. Others want options. Both are valid, and only the client can answer.

The move that beats picking for them

Here is the trick the best advisors use: take the 30-year and show the client what happens if they pay it like a 15-year voluntarily. They keep the low required payment as a safety net, but add extra principal when they can. They get most of the interest savings with none of the lock-in.

Then it is the client’s call, made on the numbers. That is the whole point of presenting options so the client decides: you are not steering them to the bigger commission or the easier sale, you are showing the tradeoff and letting the math and their life decide. In WealthLens you can put both terms side by side, with the total interest and the equity curve, and even model the extra-principal version, so the client sees all three paths at once.

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