Mortgage prepayment penalty estimate
Breaking a closed mortgage early usually costs a penalty. For fixed rates it's generally the higher of three months' interest or the interest rate differential. This is an estimate; only your lender can give the real number.
Assumptions
- 3 months' interest = balance × contract rate × 3/12.
- Simplified IRD = balance × (contract rate − comparable rate) × months left/12. Lender methods vary (posted-rate methods often give higher penalties).
- Labelled estimate; ask your lender for the exact penalty.
General information, not financial advice. This calculator gives rough estimates from simplified assumptions. It does not know your full situation. Check with a qualified professional and the official sources before making decisions.
Sources
Figures checked October 16, 2026. Rules and limits change; confirm with the source before acting.