Finance · Mortgages & Home Finance

Mortgage Recast Calculator

Estimate the payment after an entered principal reduction while retaining the rate and remaining term.

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Quick guide

How to use this calculator

  1. Enter the figures from your mortgage offer, statement, contract, property budget, or scenario.
  2. Keep currencies, rate conventions, periods, and balances consistent; compare multiple plausible scenarios where future rates or costs are uncertain.
  3. Use the component outputs to verify the result and review the calculator-specific boundary before acting.

Calculation method

Calculation method

Recast payment amortizes the post-lump-sum balance over the unchanged remaining term at the unchanged rate.

Mortgage schedules use stable level-payment arithmetic and advance only the explicitly entered scenario. Results are checked for finite, principal-reducing behavior and round only for display.

Worked example

Practical example

Apply 25,000 to a 250,000 balance with 240 months remaining.

Recast payment amortizes the post-lump-sum balance over the unchanged remaining term at the unchanged rate.

Supported inputs

Precision and limits

Visible input limits

Amounts are capped at 1e12, rates at 1000% unless a narrower percentage applies, and schedules at 1,200 months unless a frequency comparison explicitly documents more payment periods.

International scope

No currency, country, tax system, mortgage program, lender threshold, insurance rule, market rate, escrow law, or contract term is assumed.

Decision boundary

These are arithmetic scenarios, not offers, approvals, regulated disclosures, forecasts, valuations, legal interpretations, hardship advice, or recommendations.

Calculator-specific assumptions

A recast requires lender acceptance and contract-specific timing. This does not model a rate or term change.