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Owning

Extra payment

What does an extra $100 a month, or one lump sum, actually buy?

Illustrative example only — not a rate quote, not an APR offer, and not a commitment to lend.

Your inputs

The balance the extra payments are applied to.

Paid alongside the normal payment, every month, straight at the principal.

A bonus, a tax refund, a windfall — paid once.

Payment number, counting from the first one. Earlier is worth more.

Removed from the back of the loan

7 yr 6 mo

and $165,911 of interest that never gets charged, because the balance it would have been charged on is gone. An illustration produced by the inputs on this page — not a quote, not an APR, not a commitment to lend.

30 yrPayoff without the extraThe required payment is $2,686 a month.
22 yr 6 moPayoff with itYou would be sending $2,936 a month.
$542,064Interest without the extraOver the full original term.
$376,153Interest with itA difference of $165,911.

Two balances, drawn against each other

The solid line is the loan left alone. The dashed line is the same loan with your overpayments on it. The gap between them at any point is principal you no longer owe, and the year the dashed line reaches zero is the year you stop paying.

Balance as written (solid) Balance with the extra (dashed)

Where each year's money goes once you overpay

Interest is hatched, principal is solid, and this is the schedule with your overpayments in it. Watch the hatched band shrink from the very first year rather than the fifteenth — that shift is the whole mechanism, and the last column of the table below carries the same numbers in words.

Interest (hatched) Principal (solid)

Every payment, with the extra in it

The schedule your overpayments produce, not the original one. The month the table stops is the month the loan is gone. Figures are illustrative and assume the rate never changes and every payment lands on time.

Loading the schedule…

What this page assumes

  • Every extra dollar goes straight to principal. That is the only way an overpayment does anything useful, and it is not automatic — money sent without instruction is often held as a partial next payment or applied to interest first.
  • Servicers differ, and some differ badly. Some apply extra funds on the day they arrive, some at the next payment date, some only if you use a particular field on a particular form. Ask yours in writing how principal-only payments are applied, and check the next statement rather than assuming.
  • No prepayment penalty is modeled. Most owner-occupied first mortgages in the United States no longer carry one, but some loans still do, and the loan documents are the only place to find out.
  • Paying down principal does not lower the required monthly payment. The payment is fixed for the term; overpaying shortens the term instead. Recasting — re-amortizing the smaller balance over the remaining months — is a separate request that some servicers offer for a fee and that this page does not model.
  • The lump sum lands whole on the payment number you choose, and earlier is worth more than larger: a dollar applied in year one avoids interest for the whole rest of the term.
  • Taxes, insurance, HOA dues and mortgage insurance are not in this page's figures. Paying the loan down faster does end mortgage insurance sooner, which is a real saving this page does not count.
  • The rate never changes, every payment lands on time, and nothing is refinanced.
  • Every figure on this page is an illustration produced by your inputs. This site is a demonstration for a fictional lender that cannot lend.

Take this result with you

The address bar already holds every input on this page. Copy it and the result reopens exactly as you left it.

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Email it to yourself

Demonstration only. This form checks the address and shows you the confirmation a real one would show. It sends nothing, stores nothing and transmits nothing — there is no server behind this site. Use the mail-app button if you actually want the link.

Open mail app

Talk it through

Send the numbers to a person

On a live site this is where the arithmetic on the extra payment calculator turns into a conversation. A loan officer would get what you enter here, along with the inputs already in the link.

This form is a demonstration and does not send anything. There is no server, no database and no third-party form service behind this page. Nothing you type is stored, transmitted or logged, and nobody will call you. If you want to see how the real thing would behave, fill it in — it validates properly and shows the confirmation.

A real enquiry would go to (720) 555-0139 or[email protected] — both invented for this demonstration.