Mortgage Points Calculator
Reviewed by Hamza Gujjar, Algorithm Architect & Software Developer
Last updated: August 20, 2026Buying Down a Rate Is a Bet on How Long You'll Keep the Loan
Mortgage points let a borrower prepay interest upfront in exchange for a lower rate for the life of the loan — a trade that only pays off if the loan is kept long enough for the monthly savings to recover the upfront cost. Sell the home or refinance before that break-even point and the points were a net loss, no matter how attractive the lower rate looked on paper.
The Formula
New Rate = Base Rate − (Points × Rate Reduction per Point)
Break-Even (months) = Cost of Points / Monthly Payment Savings
Where This Calculation Matters
- Deciding whether to pay for points at closing — if you plan to move or refinance before the break-even month, paying for points is money that won't be recovered.
- Comparing lender offers — two lenders quoting the same rate might differ in how many points that rate costs, which changes the real cost of the loan.
- Negotiating seller-paid points — if a seller is willing to cover closing costs, points bought with their money have no break-even risk for the buyer at all.
- Long-hold vs. short-hold borrowers — someone confident they'll stay in a home 10+ years has a very different points calculus than someone expecting to relocate in three.
Break-Even Period at Different Point Purchases
On a $300,000 loan at a 7% base rate over 30 years, with each point reducing the rate by 0.25%:
| Points | Cost | New rate | Monthly savings | Break-even |
|---|---|---|---|---|
| 1 | $3,000.00 | 6.750% | $50.11 | 59.9 months |
| 2 | $6,000.00 | 6.500% | $99.70 | 60.2 months |
| 3 | $9,000.00 | 6.250% | $148.76 | 60.5 months |
In this example the break-even point lands close to 5 years regardless of how many points are purchased — a pattern that holds roughly true whenever the rate reduction per point stays constant, though it isn't a universal rule for every rate environment.
How to Use This Calculator
- Enter the Loan Amount and Base Interest Rate quoted without points.
- Enter Points Purchased and, if your lender quotes a different figure than the 0.25% default, the Rate Reduction per Point.
- Enter the Loan Term (years).
- Select Calculate to see the cost of the points, the new rate, and the break-even period in months.
Related Calculations
Compare the reduced-rate payment against a strategy of paying extra principal instead with the Extra Mortgage Payment Calculator, or check the LTV impact of your loan amount with the Loan-to-Value (LTV) Calculator.
Principles of Mortgage Discount Points and Interest Rate Buydowns
A mortgage points calculator computes the upfront cost, monthly payment savings, lifetime interest reduction, and exact financial break-even horizon when paying Mortgage Discount Points (Permanent Rate Buydowns) at loan closing. In mortgage financing, buying discount points represents paying prepaid interest upfront in exchange for a permanently lower note rate over the life of the loan.
The Fundamental Mortgage Points Formulas
Standard Rate Reduction: 1 Point (1.0% cost) typically lowers the mortgage interest rate by 0.250% (25 basis points).
Break-Even Horizon (Months) = Total Upfront Cost of Points ($) / Monthly Payment Savings ($)
Discount Points vs. Lender Credits (Negative Points)
| Rate Mechanism | Upfront Closing Cost | Ongoing Monthly Payment | Optimal Homeowner Strategy |
|---|---|---|---|
| Positive Discount Points | Pay extra upfront (1% per point) | Lower monthly payment for life | Long-term homeowners staying in the home > 7 to 10+ years |
| Zero Points (Par Rate) | $0 upfront discount fee | Standard market rate payment | Balanced standard baseline financing |
| Lender Credits (Negative Points) | Lender pays your closing costs (+$2k-$5k) | Higher monthly payment (+0.25% to +0.50% rate) | Short-term buyers selling or refinancing within 2 to 4 years |
IRS Tax Deductibility of Mortgage Points
Under IRS Publication 936, points paid on a primary residence home purchase are fully tax-deductible in the tax year paid if itemizing deductions. On a mortgage refinance, points must be amortized and deducted ratably over the 30-year loan life (e.g., deducting 1/30th per year).
Step-by-Step Worked Calculation Example
Example: Calculating the Break-Even Horizon on a $400,000 Mortgage
Problem: A borrower secures a $400,000 30-year fixed mortgage at 6.75% (Monthly P&I = $2,594.30). The lender offers to buy down the rate to 6.25% (Monthly P&I = $2,462.87) by purchasing 2.0 discount points. Calculate: (1) Upfront cost of 2 points; (2) Monthly payment savings; (3) Break-even horizon in months and years; and (4) Net 30-year lifetime savings.
Step 1: Calculate Upfront Cost of 2 Discount Points:
Points Cost = $400,000 × 0.020 = $8,000.00 Paid at Closing
Step 2: Calculate Monthly Payment Savings:
Monthly Savings = $2,594.30 - $2,462.87 = $131.43 / month
Step 3: Calculate Break-Even Period:
Break-Even Months = $8,000.00 / $131.43/month = 60.87 Months (approx. 5.07 Years)
Step 4: Calculate Net 30-Year Savings:
Gross Savings (360 mos × $131.43) = $47,314.80
Net Lifetime Savings = $47,314.80 - $8,000.00 = $39,314.80 Net Profit
Conclusion: If the homeowner keeps the mortgage longer than 5.1 years, buying points generates $39,315 in pure net interest savings.
Temporary Buydowns: The 2-1 and 3-2-1 Buydown Structure
Distinct from permanent discount points, Temporary Rate Buydowns provide steep payment relief during the initial years of homeownership:
- 2-1 Buydown (Year 1: -2.0% Rate | Year 2: -1.0% Rate | Years 3-30: Note Rate): On a 7.0% mortgage, payments are billed at 5.0% in Year 1, 6.0% in Year 2, and 7.0% in Year 3.
- Seller-Paid Concession: The $6,000 to $10,000 buydown escrow cost is typically paid entirely by home builders or property sellers as a sales incentive, providing massive initial payment savings for buyers.
Refinance Point Recapture and Early Payoff Risk
The primary risk of buying discount points is an unexpected early mortgage payoff (selling the home or refinancing into a lower rate environment before reaching the 5-year break-even date).
If a borrower pays $6,000 for points but refinances 24 months later, the unamortized points represent an irrecoverable sunk capital loss.
Rate Lock Float-Down Agreements When Paying Points
When paying discount points upfront during loan application, borrowers should negotiate a Rate Lock Float-Down Option.
If market interest rates drop significantly before closing, a float-down allows the borrower to capture the lower market rate while preserving the discount point rate reduction.
Seller-Paid Discount Point Caps
Conventional loan guidelines allow sellers to pay discount points on behalf of the buyer as part of the standard 3% to 6% seller concession allowance, reducing the buyer's monthly mortgage payment at zero out-of-pocket buyer cost.
Zero-Point Mortgage Comparison Best Practices
Always request a side-by-side Loan Estimate comparing a Zero-Point (Par Rate) loan against a 1-point and 2-point option to verify exact mathematical break-even dates before committing closing funds.