Calculator · small change, long effect
What does an extra $200 a month actually do?
Every extra dollar goes straight to principal, so it stops earning interest for the lender immediately and for every month that would have followed. The effect compounds, which is why a small amount moves the payoff date so far.
Interest you do not pay
$105,536
Paid off 6 yrs 0 mos early
- Scheduled principal & interest
- $2,246
- What you would actually send
- $2,446
- Total interest, as scheduled
- $448,535
- Total interest, paying extra
- $342,999
- Time to payoff
- 24 yrs 0 mos
- Months removed
- 72 months
- Payoff month, starting now
- —
Principal and interest only. Assumes the extra amount is applied to principal every month starting with the next payment, and that the loan has no prepayment penalty — check your note, most do not. The payoff month counts forward from today rather than from your original closing date. Estimates only, not a quote, an offer of credit, or a determination of eligibility.
Before you do it
Tell the servicer where it goes
An extra amount sent without instruction is often applied to the next scheduled payment instead of to principal, which does almost nothing. Most servicers have a principal-only field. Use it, then check the next statement.
The return is your interest rate
Every prepaid dollar avoids interest at your note rate, so the effective return is the rate itself. That makes prepayment more attractive the higher your rate is, and less attractive the lower it is — at some point the money does more good somewhere else. Where that line sits depends on your rate, your tax situation, and what the alternative use of the cash would earn.
Liquidity first
Money paid to principal is not money you can reach in an emergency without borrowing it back. Reserves, employer match, and any debt above the note rate all come before this.
Recasting is the other lever
A lump sum plus a recast re-amortizes the loan and lowers the required payment, instead of just shortening the term. Different tool for a different problem, and worth asking about.
About the starting rate. The rate control arrives pre-filled so the tool has something to calculate with. That number is a placeholder — not a quote, not a rate we have offered you, and not an offer of credit. Replace it with the rate you have actually been quoted.
For reference, the 30-year fixed average in the Freddie Mac Primary Mortgage Market Survey, retrieved from FRED (Federal Reserve Bank of St. Louis) (series MORTGAGE30US) was 6.58% for the week ending July 23, 2026, retrieved July 29, 2026. That is a national average across lenders, so no individual borrower was offered it, and it is a note rate rather than an APR — the survey does not publish APRs, and your APR will be higher than any note rate once costs are included. Your own rate depends on your credit profile, loan amount, loan-to-value, occupancy, property type, lock period and program. See the 52-week context.
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Here’s your estimated payment — want Jeff to check if it’s actually the right structure?
A calculator can tell you what a payment costs. It cannot tell you whether the term, the down payment, or the loan type is the right one for how long you plan to hold it. That part is a conversation, and it is usually a short one.
Jeff Shin · NMLS #1041652 · Barrett Financial Group, L.L.C. NMLS #181106