Updated September 2026

Mortgage Principal Curtailment 2026: How Extra Payments Save You $100,000+

Principal curtailment is the simplest wealth move most homeowners never optimize. $200 extra per month on a typical loan saves $112,000 in interest and 6 years of payments. Here's how it works, the recast trick servicers don't advertise, and the #1 mistake that wastes your extra payments.

David Rodriguez, Refinance & Rate Specialist
10 minExpert
Mortgage RefinancingRate AnalysisMarket Trends

⚡ Quick Answer

Principal curtailment = paying extra directly against your loan balance. Your monthly payment stays the same, but your term shrinks and interest savings compound.

  • 💵 $200/mo extra on $350K @ 6.5% → save $112,000, payoff 6.2 years early
  • 💰 $500/mo extra → save $205,000, payoff 11.4 years early
  • ⚠️ #1 mistake: not marking payments "principal only" — servicers default to prepaying next month instead
  • 🔄 Want a lower payment instead? That's a recast, not curtailment ($150–$500 fee)

What Is Principal Curtailment, Exactly?

Every mortgage payment splits between interest (the bank's cut) and principal (your equity). Early in a 30-year loan at 6.5%, roughly 75% of your payment is pure interest. Curtailment attacks this directly: every extra dollar goes 100% to principal, which permanently removes the interest that dollar would have generated — for decades.

Two forms:

Partial Curtailment

Any extra principal payment — $100/month recurring, annual bonus lump sums, or one-time windfalls. The most common and flexible approach.

Full Curtailment

Paying the entire remaining balance — at sale, refinance, or final payoff. Request a payoff quote from your servicer (valid 10–30 days, includes per-diem interest).

Exact Savings: $350,000 Loan at 6.5%, 30-Year Fixed

Extra PaymentInterest SavedYears CutPayoff Year
$100/month$66,0003.6 years2052
$200/month$112,0006.2 years2050
$500/month$205,00011.4 years2045
One extra payment/year (bi-weekly)$83,0004.6 years2051
$20,000 lump sum (year 2)$71,0003.3 years2052

Assumes payments start in year 1 of the loan. Starting later reduces savings — the amortization curve front-loads interest.

Run your own numbers with our free extra payment calculator — no login required. Or compare lenders to see if refinancing beats curtailment →

Curtailment vs. Recast vs. Refinance: Which One Do You Need?

FactorCurtailmentRecastRefinance
Monthly paymentSameLowerLower (if rate drops)
Loan termShorterSameResets
Cost$0$150–$5002–5% of loan
Credit checkNoNoYes
Keeps your low rateYesYesNo
Best whenYou want max interest savingsYou want lower payments, have a low rateRates dropped 0.75%+ below yours

The pro combo: curtail aggressively, then request one recast to capture a lower required payment while keeping the shortened payoff trajectory. See our mortgage recasting guide.

If your rate is above 7%, refinancing may beat curtailment entirely. Check today's refinance rates → — if you can drop 0.75%+, run that math first.

Is Curtailment or Refinancing Cheaper for You?

Takes 2 minutes to compare: your current loan vs. extra payments vs. today's refinance rates.

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5 Curtailment Mistakes That Waste Your Money

  1. 1.
    Not marking "principal only." By default, many servicers hold extra funds as your next payment — saving you nothing. Always select "apply to principal" and verify on your next statement.
  2. 2.
    Curtailing before killing high-interest debt. A 24% credit card always beats a 6.5% mortgage. Clear cards first.
  3. 3.
    Draining your emergency fund. Principal payments are one-way — you can't un-pay them without a HELOC or refinance. Keep 3–6 months liquid first.
  4. 4.
    Paying for a bi-weekly "program." Servicers charge $300–$400 to set up bi-weekly payments. DIY it free: add 1/12 of your payment to each month as principal-only.
  5. 5.
    Ignoring the invest-vs-curtail math. At a 3% pandemic rate, index funds likely win. At 6.5%+, curtailment is a guaranteed return no fund can promise. See pay off mortgage vs invest.

Should You Refinance Instead of Curtailing?

If today's rates are 0.75%+ below yours, refinancing could save more than a decade of extra payments. Compare free in 2 minutes.

Check My Refinance Savings →

Frequently Asked Questions

What is mortgage principal curtailment?

Principal curtailment means making payments directly against your loan balance beyond your required monthly payment. A partial curtailment is any extra principal payment ($100/month extra or a $10,000 lump sum); a full curtailment pays the loan off entirely. Curtailment shortens your loan term and cuts total interest — your required monthly payment stays the same.Check your personalized rate →

What is the difference between curtailment and recasting?

Curtailment shortens your loan term but keeps your monthly payment the same. Recasting (re-amortization) keeps your term but lowers your monthly payment after a lump-sum payment — usually $5,000+ minimum and a $150–$500 fee. Curtailment saves more total interest; recasting improves monthly cash flow. Many homeowners curtail first, then recast once.Check your personalized rate →

How much does an extra $200/month save on a mortgage?

On a $350,000 loan at 6.5% for 30 years: an extra $200/month saves about $112,000 in interest and pays the loan off 6.2 years early. An extra $500/month saves about $205,000 and cuts 11.4 years. The earlier you start, the bigger the savings because early payments attack the highest-interest portion of the amortization curve.Check your personalized rate →

Is principal curtailment better than investing?

It depends on your rate. With a mortgage at 6.5–7%, curtailment is a guaranteed 6.5–7% return — competitive with the stock market's historical 7–10% but with zero risk. With a 3% pandemic-era mortgage, investing usually wins. Rule of thumb in 2026: curtail if your rate is above 5.5%, invest if below 4.5%, split if in between.Check your personalized rate →

Do extra principal payments lower your monthly payment?

No — this is the most common misconception. Extra principal payments shorten your loan term but your required payment stays identical. To lower the monthly payment after a big principal payment, you need to request a recast from your servicer (small fee, no credit check) or refinance.Check your personalized rate →

How do I make sure extra payments go to principal?

Specify "apply to principal" explicitly — by default, many servicers apply extra money to next month's payment (prepaying interest) instead. Use the principal-only option in your servicer's online portal, or write "principal only" on checks. Then verify your balance dropped by the full amount on your next statement.Check your personalized rate →

Paying 7%+? Refinancing May Beat Curtailment

If today's rates are 0.75% below yours, a refi could save more than a decade of extra payments.

Free comparison • 2 minutes • No hard credit pull

Compare My Refinance Savings →

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