buy points calculator

What does “buying points” mean?

Buying mortgage points (also called discount points) means paying an upfront fee at closing in exchange for a lower interest rate. Each point usually costs 1% of the loan amount. On a $400,000 loan, one point costs about $4,000.

The key question is simple: Will the lower monthly payment and reduced interest add up to more than the upfront cost? This calculator helps you answer that with a clear break-even estimate and net savings projection.

How this buy points calculator works

1) It compares two loan scenarios

• Scenario A: Mortgage without points (higher rate, no upfront point cost)
• Scenario B: Mortgage with points (lower rate, upfront point cost)

2) It estimates monthly payment difference

You’ll see how much the payment changes when the interest rate drops. This is useful for cash-flow planning, but it is not the whole story.

3) It computes true break-even timing

Instead of using a rough shortcut, this tool tracks month-by-month interest savings and identifies when cumulative savings exceed your upfront point cost.

4) It checks your expected holding period

If you plan to refinance, move, or pay off the loan before break-even, buying points often doesn’t make financial sense. The calculator highlights this directly.

When buying points may make sense

• You expect to keep the mortgage long enough to pass break-even.
• You want lower monthly payments and predictable long-term savings.
• You have enough cash at closing without draining emergency reserves.
• The offered rate reduction is meaningful relative to point cost.

When buying points may not make sense

• You may move or refinance in the next few years.
• You’re tight on cash and need liquidity more than payment reduction.
• The lender’s rate drop for points is very small.
• You can deploy that upfront money to higher-priority debt or emergency savings.

Quick interpretation guide for your results

• Break-even month: The month where cumulative interest savings catch up to point cost.
• Net benefit over your timeline: Interest saved minus point cost during your expected stay.
• Full-term comparison: Useful for long-term borrowers, less useful if you’ll refinance early.

Important caveats

This calculator is intentionally practical, but still simplified. Real-life loan decisions can include taxes, lender credits, PMI changes, refinancing costs, and opportunity cost of cash. Treat this as a decision aid—not personalized financial advice.

Bottom line

Buying points can be a smart move when your time horizon is long enough and the rate reduction is strong enough. Use the calculator, focus on break-even, and make sure the upfront cost fits your broader financial plan.