Mortgage Penalty Estimator
Estimate early-payout penalties using 3-month interest and a simple IRD model. Apply a one-time prepayment, or auto-calc months from a maturity date. Export CSV or a branded printout.
Quick Results
Effective Balance (after prepayment)$520,000
Remaining Term Used24 months
3-Month Interest$6,357
IRD (Simple)$15,600
Base Penalty (per rule above)$15,600
Admin / Discharge Fee$300
Estimated Total$15,900
Assumptions & Notes
- 3-Month Interest = Effective Balance × Contract Rate × (3/12).
- IRD (simple) = Effective Balance × (Contract − Comparison) × (Remaining Months ÷ 12).
- Lenders may use posted vs. discounted rate methods, exact day-counts, amortization left, or other rules. Your agreement governs.
- Prepayment privileges vary (and may reset annually). Some products (open, blend-and-extend, portability) can change or reduce penalties.
- This tool is an estimate and not financial advice.
3-Month Interest Detail
Typically used for variable-rate mortgages or when it’s greater for fixed-rate penalties.
Effective Balance$520,000
Contract Rate4.89%
Penalty (3 months)$6,357
IRD (Simple) Detail
This estimate compares your contract rate to a current comparable term rate.
Effective Balance$520,000
Contract Rate4.89%
Comparison Rate3.39%
Remaining Term24 months
Penalty (IRD)$15,600