10-Year Fixed Mortgage Calculator

What this calculator adds up: four lines, not one

A mortgage quote usually leads with one number, the principal and interest. The payment that leaves your account every month has up to four lines: principal, interest, private mortgage insurance and the escrow share of property taxes and homeowner's insurance. Lenders group the first two under P&I and the last two under escrow, and the Consumer Financial Protection Bureau calls the whole stack PITI (CFPB). A 10-year fixed mortgage makes the gap between the advertised number and the real number unusually visible, because the short term already pushes the P&I line close to what a borrower expected to pay in total.

On the example used throughout this page, a $300,000 loan at 6.5% over 10 years, the P&I line is $3,406.44. Add a $125.00 PMI premium and $425.00 of escrow and the payment due is $3,956.44. The widget below computes all four lines from a home value, a down payment, a rate, a tax bill, an insurance premium and a PMI rate, then reports amortization progress, the effect of extra payments and a refinance break-even.

Every line behaves differently over time. Principal and interest are fixed for 120 months on a fixed rate. PMI can disappear partway through. Escrow moves whenever the tax assessor or the insurer moves. That is why this page keeps the lines apart instead of folding them into a single estimate.

The principal and interest core, worked step by step

Both pieces of the P&I line come from one formula: the balance times the monthly rate, divided by one minus (one plus the monthly rate) raised to the power of minus 120. The monthly rate here is 0.065 / 12 = 0.0054167. Feed in the example numbers and the payment is $3,406.44, fixed for all 120 months.

The split inside that payment changes every month. In month one the interest piece is 300,000 x 0.0054167 = 1,625.00, so the principal piece is 3,406.44 - 1,625.00 = 1,781.44. This is the quiet advantage of a 10-year schedule: principal outruns interest from the first month. On a 30-year amortization the same loan would spend its first years paying mostly interest.

By month 60 the balance has fallen enough that interest is only $956.31 and the principal piece is 3,406.44 - 956.31 = 2,450.13. By the final payment interest is down to $18.35. The total of all 120 payments is $408,772.72, so the interest bill is $108,772.72, and none of that total changes if the rate is fixed and every payment is on time.

Amortization progress on a 120-month clock

Progress is the number most 10-year borrowers care about most: how much of the debt is gone, and how fast. On this schedule the balance crosses from $300,000 to $254,473 in the first two years, which retires 15.2% of the principal. By the end of year 5 the balance is $174,099 and 42.0% of the principal is gone. The last two years retire 26.8 points on their own, from 86.8% at the end of year 9 to the final payment.

Two consequences follow. First, equity builds fast enough that PMI (below) has a short life on this schedule. Second, refinancing or selling in the early years forfeits most of the progress: a borrower who sells at year 3 has only retired $70,601 of principal despite paying $122,632 toward the loan. The chart shows the shape the widget reports as its amortization line.

PMI: the line that appears under 80 percent loan-to-value

On a conventional loan, a down payment under 20% of the home's value usually means private mortgage insurance. The premium protects the lender, not the borrower, and it is quoted as an annual percentage of the loan balance divided into twelve monthly pieces. The example home is worth $340,000 with $40,000 down, so the loan is $300,000 and the loan-to-value ratio is 88.2%. At an illustrative 0.5% annual premium, the cost is 0.005 x 300,000 = 1,500 a year, and 1,500 / 12 = 125.00 a month.

The premiums in the table are worked examples, not quotes: insurers set the real rate from credit score, LTV and coverage level. The cancellation rules, however, are law. Under the Homeowners Protection Act rules the CFPB explains, you can request cancellation in writing once the balance is scheduled to fall to 80% of the home's original value, the servicer must terminate it automatically at 78%, and it must end at the midpoint of the amortization schedule regardless.

On a 10-year schedule that 80% point arrives quickly. The balance falls below 80% of $340,000, which is $272,000, during the second year, so a written request can end this $125.00 line earlier than almost any other mortgage shape.

Escrow: taxes and insurance sharing the same payment

Escrow is a holding account the servicer uses to pay property taxes and homeowner's insurance on your behalf. The CFPB's escrow explainer describes why many lenders require it on low-down-payment loans: the bill gets paid, and the servicer can see it. The monthly escrow line is the year's tax bill and premium divided by twelve, plus whatever cushion the servicer's annual analysis requires. That cushion is capped by federal rule: HUD's RESPA settlement booklet states that a servicer may hold no more than two months of escrow payments in reserve.

The example assumes a $3,600 annual tax bill and a $1,500 insurance premium. The escrow line is 3,600 / 12 = 300.00 plus 1,500 / 12 = 125.00, which is $425.00 a month. Neither number is fixed by the loan: the assessor can raise the tax, the insurer can raise the premium, and the escrow line moves with them even though the P&I line never moves.

That asymmetry is worth noticing on a 10-year loan. The P&I piece is contractually frozen for 120 months, but a borrower who budgets the P&I figure alone can be short by hundreds within two tax cycles. Enter the current tax bill and premium in the widget and re-enter them every year after the servicer's escrow analysis arrives.

Extra payments and the biweekly switch

Extra principal is the one lever that works on every line of the loan at once: each dollar sent early stops accruing interest for the rest of the schedule. On a 10-year loan the savings are smaller than on a 30-year loan, because there is less time left for interest to accrue, but the acceleration is dramatic.

The biweekly plan splits each month's payment in half and pays every two weeks, so 26 half payments deliver 13 full payments a year. The extra principal is 3,406.44 / 12 = 283.87 a month, and the loan ends in 108 months instead of 120, a saving of $10,219.32. Check the note for a prepayment penalty and instruct the servicer in writing that extra money goes to principal, not to next month's payment.

Refinance break-even: months to recover the costs

Refinancing trades closing costs for a different payment, and the honest comparison is a calendar, not a rate. Break-even months are the closing costs divided by the monthly saving. The example: a borrower three years into a 30-year loan at 7.24%, the Freddie Mac 30-year average for the week ending October 29, 2026 on the Primary Mortgage Market Survey, owes $290,603. A 6.25% refinance over a new 30-year term costs 2,044.49 - 1,789.29 = 255.20 less per month. With $4,500 of closing costs, the break-even is 4,500 / 255.20 = 17.6 months.

Three checks sit around that number. If you may sell before month 17.6, the refinance loses money. If the new loan pushes the balance back over 80% LTV, PMI returns and shrinks the saving, since refinancing with less than 20% equity normally means insuring the lender again. And shortening the term changes the comparison entirely: switching that same balance into a 10-year fixed raises the payment but cuts the interest over the next ten years from roughly $213,609 to $105,366, which is a wealth decision, not a cash-flow one.

The widget computes the same arithmetic from your current payment, your remaining balance, the new rate and term, and the cost quote, and reports the break-even in months.