Free real estate calculator

Mortgage Recast Calculator

Compare a recast with extra principal and refinancing over the remaining term.

By Calculate My Property EditorialUpdated September 30, 2026Professional review pending
01 / Your inputs

Start with your property.

Property4 inputs
USD
USD
USD
USD
Current loan2 inputs
%
Recasting keeps the rate.
years
Recast keeps this remaining term.
Refinance comparison1 inputs
%
Comparison uses the same remaining term.
All amounts in USD.
Your estimate

New recast monthly P&I

$1,688Based on your inputs · USD
Monthly payment reduction
$338
Refinance monthly P&I
$1,611
Extra-principal payoff time
205 months
The formula

New payment on reduced principal at unchanged rate and term

Assumptions & limitations (1)
  • Refinance costs are paid in cash; term stays the same. Extra-principal comparison applies the same lump sum and keeps the old payment. Availability and minimum curtailment depend on lender.
02 / Your next decisionExtra Payment PayoffBridge Loan
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Planning estimate. Editorially sourced; independent professional review is pending. How we calculate
The detail

Your calculation table

3 rows · full data in CSV
OptionMonthly P&IIncremental fees
Recast1,688.02300
Refinance1,610.756,000
Lump sum, keep old payment2,025.620
Worked example

Follow the default numbers.

With current principal balance of $300,000, the model gives new recast monthly p&i: $1,688.

The formula is new payment on reduced principal at unchanged rate and term. Open the breakdown to trace expenses and assumptions. Change one input at a time to see how your decision changes. This example uses scenario inputs; it is not an offer, tax bill, appraisal or legal determination.

A recast changes the payment, not the rate

The estimate subtracts the lump-sum principal payment from current balance and calculates a new payment at the existing note rate over the remaining term. The lender’s recast fee is separate. Eligibility, minimum curtailment and timing depend on the loan and servicer. The tool assumes a fixed-rate amortizing loan with no prepayment penalty.

Keep paying the old payment

Without a recast, applying the same lump sum and continuing the original payment can pay the loan off sooner. The comparison models that path and shows months and interest. Recasting reduces the required payment but keeps the original remaining term; it does not create the same payoff acceleration unless you continue paying extra.

Refinancing adds a new cost decision

The refinance comparison uses the reduced balance, entered new rate and same remaining term. It assumes closing costs are paid in cash. A lower payment alone does not establish savings, especially if a real refinance extends the term. Compare total remaining interest and incremental fees before choosing which use of sale proceeds fits your goals.

Keep your assumptions with the result

Save the calculation to your deal file to reuse compatible inputs in another tool. The file stays in this browser on this device. Download the CSV to open the complete inputs, results and schedule in Excel or Google Sheets. Use PDF to print the report or save it as a PDF. A share link includes entered financial figures in its URL, so use it only with people you intend to share those numbers with.