Permanent Buydown Calculator Excel






Permanent Buydown Calculator Excel | Calculate Your Breakeven Point


Permanent Buydown Calculator

Analyze the costs and benefits of permanently buying down your mortgage rate.



The total amount of your mortgage.

Please enter a valid loan amount.



The interest rate without paying for points.

Please enter a valid interest rate.



1 point costs 1% of the loan amount. Lenders often reduce the rate by 0.25% per point.

Please enter a valid number of points.



The percentage the rate is reduced for each point purchased. Typically 0.25%.

Please enter a valid rate reduction.



The length of your mortgage, typically 15 or 30 years.

Please enter a valid loan term.


Breakeven Point

Buydown Cost

New Interest Rate

Monthly Savings

Formula Used: The breakeven point is calculated by dividing the total upfront cost of the discount points by the monthly savings you gain from the lower interest rate. Breakeven (Months) = Buydown Cost / Monthly Savings. This shows how long it takes to recover your initial investment.


Amortization Comparison: First 5 Years
Year Original Rate Payment New Rate Payment Annual Savings

Chart: Total Interest Paid Over Loan Term

What is a Permanent Buydown?

A permanent buydown, often discussed in the context of “permanent buydown calculator excel,” is a financial strategy where a homebuyer pays an upfront fee to a lender to lower the interest rate for the entire life of the loan. This fee is paid in the form of “mortgage points” or “discount points,” where one point typically costs 1% of the total loan amount. By purchasing these points, the borrower secures a lower fixed monthly payment, leading to significant interest savings over the long term. This contrasts with a temporary buydown (like a 2-1 buydown), where the rate is only reduced for the first few years.

This strategy is ideal for buyers who plan to stay in their home for many years. The core decision revolves around the breakeven point—the time it takes for the monthly savings to offset the initial cost of the points. A detailed permanent buydown calculator, much like an advanced excel model, is essential for this analysis. A common misconception is that buydowns are always a good deal, but if you sell or refinance before the breakeven point, you will lose money on the transaction.

Permanent Buydown Formula and Mathematical Explanation

Understanding the math behind a permanent buydown is crucial. The two key formulas are for the monthly mortgage payment and the breakeven point. Our permanent buydown calculator excel tool automates this for you.

1. Monthly Mortgage Payment (M): This is calculated using the standard amortization formula:

M = P [i(1 + i)^n] / [(1 + i)^n - 1]

2. Breakeven Point (Months): This is the most important calculation for a buydown decision.

Breakeven Point = Total Buydown Cost / Monthly Savings

Variable Explanations
Variable Meaning Unit Typical Range
P Principal Loan Amount Dollars ($) $100,000 – $1,000,000+
i Monthly Interest Rate (Annual Rate / 12) Percentage (%) 0.2% – 0.7%
n Number of Payments (Loan Term in Years * 12) Months 180 (15yr), 360 (30yr)
Buydown Cost (Loan Amount * Points) / 100 Dollars ($) $2,000 – $20,000+
Monthly Savings Original Payment – New Payment Dollars ($) $50 – $500+

Practical Examples (Real-World Use Cases)

Example 1: Long-Term Homeowner

A family buys a home with a $400,000 loan at a 7% interest rate for 30 years. They plan to live there for at least 15 years. The lender offers to lower the rate to 6.5% for 2 discount points.

  • Inputs:
    • Loan Amount: $400,000
    • Original Rate: 7.0%
    • Points: 2 (costing 2% of $400,000 = $8,000)
    • New Rate: 6.5%
  • Outputs (from a permanent buydown calculator):
    • Original Monthly Payment: $2,661
    • New Monthly Payment: $2,528
    • Monthly Savings: $133
    • Breakeven Point: $8,000 / $133 ≈ 60 months (5 years)
  • Interpretation: Since the family plans to stay well beyond the 5-year breakeven point, this is a financially sound decision. Over 30 years, they would save over $40,000 in interest.

Example 2: Potential for Relocation

An individual secures a $500,000 mortgage at 6.8% for 30 years. They might be relocated for work within 3-4 years. The lender offers to lower the rate to 6.3% for 2.5 points.

  • Inputs:
    • Loan Amount: $500,000
    • Original Rate: 6.8%
    • Points: 2.5 (costing 2.5% of $500,000 = $12,500)
    • New Rate: 6.3%
  • Outputs (from a permanent buydown calculator excel model):
    • Original Monthly Payment: $3,259
    • New Monthly Payment: $3,094
    • Monthly Savings: $165
    • Breakeven Point: $12,500 / $165 ≈ 76 months (6.3 years)
  • Interpretation: The breakeven point is over 6 years away. Since they might move before then, paying for the buydown is risky. They would likely lose money if they sell the house in year 4. Check out our refinance calculator to explore other options.

How to Use This Permanent Buydown Calculator

Our tool simplifies the complex analysis often done in a permanent buydown calculator excel sheet. Follow these steps for an accurate analysis:

  1. Enter Loan Amount: Input the total mortgage principal.
  2. Enter Original Interest Rate: This is the “par” rate offered by the lender without any points.
  3. Enter Discount Points: Input the number of points you are considering purchasing (e.g., 1, 1.5, 2).
  4. Enter Rate Reduction: Input how much the rate drops per point (usually 0.25%).
  5. Enter Loan Term: Provide the mortgage term in years (e.g., 30).

The calculator instantly updates, showing you the breakeven point. If you plan to stay in the home longer than the breakeven period, the buydown is generally a good investment. If not, you are better off keeping the cash or using it for a larger down payment. Our amortization schedule calculator can provide a more detailed breakdown.

Key Factors That Affect Permanent Buydown Results

The decision to buy down a rate isn’t just about the numbers. Several factors influence whether it’s the right choice for you.

  • Time in Home: The most critical factor. The longer you stay past the breakeven point, the more you save.
  • Upfront Cost: Do you have the cash available for the points? This money could otherwise be used for a down payment, investments, or an emergency fund. Explore options with our investment calculator.
  • Interest Rate Environment: If rates are high but expected to fall, you might refinance in a few years anyway, making a buydown a poor choice. Conversely, if rates are low and expected to rise, locking in an even lower rate permanently is attractive.
  • Lender’s Offer: The cost of points versus the rate reduction varies by lender. Shop around to find the best deal. Some lenders may offer better par rates than others offer bought-down rates.
  • Financial Goals: If your primary goal is the lowest possible monthly payment for budget stability, a permanent buydown is very effective. If your goal is to minimize upfront cash at closing, you should avoid it.
  • Refinancing Plans: If you plan to refinance your mortgage in the near future, paying for a permanent buydown is a waste of money as the benefit is lost upon refinancing. Our mortgage payoff calculator can help you weigh these decisions.

Frequently Asked Questions (FAQ)

1. What’s the main difference between a permanent and temporary buydown?

A permanent buydown lowers the interest rate for the entire loan term. A temporary buydown (e.g., 2-1 buydown) only lowers the rate for the first 1-3 years, after which it returns to the original, higher rate. A permanent buydown calculator is essential to compare against temporary options.

2. Who pays for the buydown points?

Typically the borrower pays. However, in some markets, sellers or builders may offer to pay for points as a concession to make the deal more attractive. This is a point of negotiation.

3. Is the cost of discount points tax-deductible?

Yes, in most cases, mortgage discount points are considered prepaid interest and can be tax-deductible in the year they are paid. Consult with a tax professional for advice specific to your situation.

4. How is a permanent buydown different from a larger down payment?

A larger down payment reduces the principal loan amount, which lowers your monthly payment and saves on interest. A buydown keeps the loan amount the same but reduces the interest rate. Which is better depends on the numbers; our permanent buydown calculator excel tool helps you compare.

5. Can I buy a fraction of a point?

Yes, many lenders allow you to purchase points in fractions, such as 0.25 or 0.125 points, allowing for more precise control over your upfront costs and rate reduction.

6. What happens to my points if I refinance?

You lose the benefit of the points you paid for. When you refinance, you are paying off the old loan and starting a new one. This is why it’s critical to only buy points if you are confident you won’t refinance before the breakeven point.

7. Is there a limit to how many points I can buy?

This depends on the lender. Most lenders have a cap on the number of points you can purchase, often around 3-4 points. The value proposition also diminishes after a certain point.

8. Why use a permanent buydown calculator instead of a simple spreadsheet?

While an Excel sheet can work, a dedicated permanent buydown calculator like this one is built to handle the specific formulas, provide instant results, generate charts, and prevent common errors, giving you a more reliable and user-friendly analysis.

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