An amortization schedule is the month-by-month map of a fixed-payment loan: how much of each payment goes to interest, how much chips away at what you owe, and what’s left afterward. On a 30-year mortgage at today’s rates, the very first payment is close to 90% interest. Seeing that split in black and white is usually the moment people start making extra payments.
The free generator below builds a complete monthly or yearly schedule for any loan, shows the effect of extra monthly payments or a one-time lump sum, draws your balance over time, and downloads the whole table as a CSV file that opens in Excel or Google Sheets. Below it, you’ll find the formulas behind the numbers, real examples at current rates, and answers for situations like removing PMI, refinancing midstream and paying off a car loan early.
Free Amortization Schedule Generator With Extra Payments
Enter your loan details. The schedule, chart and savings update as you type. Switch between monthly and yearly views, or download the full table for Excel.
Optional extra payments
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Payments are rounded to the cent and the final payment is adjusted so the balance reaches exactly zero. Mortgage figures exclude property taxes, homeowners insurance and mortgage insurance, which are often collected in the same monthly bill. The highlighted row marks when principal first exceeds interest.
We checked the generator against two outside benchmarks. First, against Excel’s own PMT function: a $400,000, 30-year loan at 7.18% returns $2,709.74 in both. Second, against market data: entering Edmunds’ latest averages for a financed used car, $30,703 at 10.6% for 72 months, produced a payment of about $578, within a few dollars of the $582 average payment Edmunds reported for the same quarter. The small gap reflects that real loans mix different amounts, rates and terms.
Eight Straight Answers About Amortization Schedules
The questions people type into search right after they see their first schedule. Short answers first; the details follow.
A table showing every payment on a fixed-payment loan, split into interest and principal, with the remaining balance after each one.
Interest is charged on the balance, and the balance is largest at the start. As it shrinks, more of the same payment goes to principal.
Yes, especially early. Every extra principal dollar stops earning interest for the rest of the loan.
Yes. Use PMT for the payment, IPMT and PPMT for each split, or download a ready-made schedule from the generator above.
Usually not. It shortens the loan instead. A lender recast can lower the payment after a large lump sum, for a fee.
On most newer mortgages, only in the first three years and capped at 2% or 1% of the balance. Check your loan documents.
Not exactly. A payoff quote adds interest through the payoff day and any fees. Always request an official payoff statement.
Most use simple daily interest, so paying early or late each month shifts the split slightly from the printed schedule.
How a Fixed Monthly Payment Is Split, Month by Month
Every row of a schedule follows the same three steps. Once you see them, the whole table makes sense.
Interest for the month
Take the current balance and multiply by the annual rate divided by 12. On $400,000 at 7.18%, that’s $400,000 × 0.0718 ÷ 12 = $2,393.33 for the first month.
Principal paid
Subtract that interest from your fixed payment. With a $2,709.74 payment, $316.41 goes to principal. Any extra payment is added straight to this number.
New balance
Subtract the principal from the old balance: $400,000 − $316.41 = $399,683.59. Next month’s interest is figured on that smaller number, and the cycle repeats until the balance reaches zero.
We found the crossover point is the single most useful line on any long schedule. In this example, principal doesn’t overtake interest until payment 245, more than twenty years in. By then you’ve paid about $487,000 in interest and only about $174,000 of principal. That’s why extra payments made in the first decade do so much work, and why restarting a 30-year clock with a refinance should be weighed carefully.
The payment itself comes from one formula. With P the loan amount, r the monthly rate (annual rate ÷ 12) and n the number of payments, the fixed payment is P × r ÷ (1 − (1 + r)−n). Every amortization calculator, every lender system and Excel’s PMT function use this same equation. If the rate is zero, the payment is simply the loan amount divided by the number of payments.
What Extra Payments Actually Save
An extra payment doesn’t just reduce today’s balance. It removes that money from every future interest calculation for the life of the loan.
The pattern held across every loan we ran: the earlier an extra dollar arrives, the more interest it erases. On our $400,000 example, $200 a month starting in month one saves about $132,000. The same $200 started in year 15 saves far less, because by then the remaining balance and the remaining time are both smaller. Try it in the generator by putting the money in as a lump sum at different payment numbers.
Biweekly payments work because 26 half-payments equal 13 full payments a year, one more than the usual 12. You can get the same effect, without enrolling in anything, by adding one-twelfth of your payment to each monthly bill. Be wary of third-party biweekly services that charge setup or per-payment fees; some simply hold your money and forward it once a month.
Shorter terms beat extra payments on rate. A 15-year loan usually carries a lower rate. At this month’s averages, $400,000 over 15 years at 6.57% costs about $3,500 a month and about $230,000 in total interest, compared with about $575,500 on the 30-year. The trade-off is a required payment about $790 higher. Many borrowers prefer the 30-year’s flexibility and prepay voluntarily, knowing they can stop in a tight month.
Prepayment penalty. For most mortgages made since 2014, federal rules allow a penalty only on certain fixed-rate qualified mortgages, only in the first three years, and capped at 2% of the prepaid balance in years one and two and 1% in year three. How the servicer applies it. Write “apply to principal” on the payment or use the servicer’s principal-only option, then confirm on your next statement. Higher-cost debt first. Paying down a 22% credit card or building an emergency fund usually beats prepaying a 7% mortgage.
How to Build a Loan Amortization Schedule in Excel or Google Sheets
Five functions do the heavy lifting. They work the same way in Excel and Google Sheets.
| Function | What it returns | Example for $400K, 30 yr, 7.18% | Result |
|---|---|---|---|
| PMT | Fixed payment | =PMT(7.18%/12,360,-400000) | $2,709.74 |
| IPMT | Interest in a given payment | =IPMT(7.18%/12,1,360,-400000) | $2,393.33 |
| PPMT | Principal in a given payment | =PPMT(7.18%/12,1,360,-400000) | $316.41 |
| CUMIPMT | Total interest over a range | =CUMIPMT(7.18%/12,360,400000,1,12,0) | −$28,593 (year 1) |
| NPER | Payments needed at a given amount | =NPER(7.18%/12,-2909.74,400000) | ~290 (with $200 extra) |
A simple five-column schedule
Set up your inputs
Put the loan amount in B1, the annual rate in B2, the number of payments in B3 and the payment in B4 using =PMT(B2/12,B3,-B1). Round it with =ROUND(PMT(B2/12,B3,-B1),2) so it matches a real bill.
Create the columns
In row 6, label Payment #, Interest, Principal, Extra and Balance. In row 7, start with payment 1, and in the Balance column of row 6 enter the opening balance =B1.
Write the row formulas
Interest: =ROUND(E6*$B$2/12,2). Principal: =MIN($B$4-B7+D7,E6), where D7 is any extra payment. Balance: =E6-C7. Copy the row down until the balance hits zero.
Add totals and a payoff date
Sum the interest column for lifetime interest. Use =EDATE(start_date,payment_number-1) to show the calendar month of each payment. Or skip the setup entirely and download the CSV from the generator, which opens directly in Excel or Sheets.
When we built the same schedule by hand in a spreadsheet, the only mismatch with lender statements came from rounding. Lenders round each month’s interest to the cent, which can make the final payment a few cents different from the others. Our generator and the spreadsheet steps above both round monthly and adjust the last payment, so the balance ends at exactly zero.
How Amortization Works on Each Type of Loan
The math is the same, but the fine print isn’t. These differences decide how well a printed schedule matches your real balance.
| Loan type | How interest is charged | Prepayment penalty? | Extra payment tip | Watch out |
|---|---|---|---|---|
| Fixed-rate mortgage | Monthly, on the balance | Only limited cases, first 3 years | Mark extras “principal only” | Bill also includes taxes and insurance |
| Adjustable-rate mortgage | Monthly; rate resets | Generally not allowed on newer loans | Prepay before resets | Schedule changes at every reset |
| Auto loan | Usually simple daily interest | Rare | Pay a few days early each month | Late payments add interest |
| Personal loan | Daily or monthly | Check contract | Ask how extras are applied | Origination fee isn’t in the schedule |
| Federal student loan | Daily simple interest | None | Target the highest-rate loan | Income-driven plans don’t follow a standard schedule |
| HELOC (draw period) | Variable; often interest-only | Some charge early-closure fees | Pay principal during the draw | Payment jumps when the draw ends |
Federal law bars the old “Rule of 78s” interest method, which front-loads interest even more heavily, on consumer loans with terms longer than 61 months. You may still see it on some shorter loans, where it can make early payoff less rewarding than a normal schedule suggests. If your contract mentions precomputed interest or the Rule of 78s, ask the lender how a payoff would be calculated before you prepay.
How Much the Interest Rate Reshapes Your Schedule
A single percentage point doesn’t sound like much. Spread across 360 payments, it changes everything below the payment line.
When we ran one $400,000 loan through the generator at five different rates, the monthly payment moved by a few hundred dollars per point, but lifetime interest moved by tens of thousands. Going from 6.5% to 7.18%, roughly the gap between a strong rate quote and the current average, adds about $182 a month and about $65,000 over the life of the loan. The share of the first payment that goes to interest also climbs, from 86% to 88%, so equity builds more slowly in the early years.
That’s why shopping for a rate is one of the highest-value hours you’ll spend on a loan. Get written loan estimates from at least three lenders on the same day, compare the rate and the points, and run each one through the generator. A lender charging a slightly higher rate with no points can come out ahead if you expect to sell or refinance within a few years, while paying points for a lower rate rewards borrowers who keep the loan a long time.
Rates also explain why an amortization schedule for an adjustable-rate mortgage is only a forecast. The schedule is accurate for the fixed period. At each reset, the lender recalculates the payment using the new rate, the remaining balance and the remaining term, which creates a brand-new schedule from that point. To stress-test an adjustable loan, run the generator a second time starting from the balance at the first reset, using the highest rate your loan’s caps allow.
Auto and personal loans follow the same pattern at a smaller scale. A $30,703 used-car loan over 72 months costs about $10,900 in interest at the recent 10.6% average. A borrower who qualifies for a rate several points lower, or who chooses 48 months instead of 72, can cut that figure dramatically. Credit unions and preapproval before visiting a dealer are the two most reliable ways to get there.
Which Situation Sounds Like Yours?
A schedule is most useful when it answers a specific decision. Here’s how to read yours for the situations we hear about most.
On a conventional loan, federal law lets you ask to cancel PMI once your balance is scheduled to reach 80% of the home’s original value, if your payment history is good, and requires automatic cancellation at 78%. Your schedule shows exactly when. In our example with 10% down on a $444,444 home, the 80% mark arrives at payment 103 on the regular schedule, but at payment 61 with $300 a month extra, more than three years sooner. Prepaying lets you request cancellation early; the automatic 78% date follows the original schedule.
Find your current row on the schedule and note how many payments are left. A new 30-year loan restarts the clock, so even a lower rate can raise total interest if you’re already ten years in. Compare the remaining interest on your current schedule with the total interest plus closing costs on the new one, or refinance into a shorter term that ends near your original payoff date.
A lump sum to principal shortens the loan but keeps the same payment. If you’d rather lower the payment, ask your servicer about a recast: the lender re-amortizes the smaller balance over the remaining term for a one-time fee. Conventional loans often allow it; FHA and VA loans generally don’t. Enter the lump sum in the generator to see both the time saved and the new balance.
Set the payoff date you want, then raise the extra monthly payment in the generator until the schedule ends by then. Weigh it against retirement contributions, especially any employer match, and keep enough cash on hand that you aren’t forced to borrow at higher rates in a surprise.
Cars lose value fastest in the first years, exactly when the schedule pays down the least principal. A long, high-rate loan makes the gap worse. Use the generator to see when your balance drops below the car’s likely value, and add a small extra payment if you may need to sell or trade in early.
The schedule balance is a planning number, not the amount needed to close the loan. Ask the servicer for an official payoff statement good through a specific date; it includes interest up to that day and any fees. Mortgage servicers must respond to a written payoff request within a short legal deadline, typically seven business days.
During an interest-only draw period, the balance doesn’t fall unless you add principal. When repayment starts, the remaining balance amortizes over a shorter period, and the payment can jump sharply. Plug the balance, rate and repayment years into the generator now so the new payment isn’t a surprise.
A schedule assumes on-time payments; missed ones add interest and fees and can trigger default. Call your servicer as soon as you see trouble coming and ask about loss mitigation options. A HUD-approved housing counselor can help free of charge, and you should be wary of anyone who asks for an upfront fee to save your home.
Five Reasons Your Real Balance Won’t Match a Schedule
If your statement and your spreadsheet disagree, one of these is almost always the cause.
The second item causes the most frustration. Some servicers treat extra money as an early version of next month’s payment rather than a principal reduction, which saves you almost nothing. Look for a separate “additional principal” line on your statement after any extra payment. If it isn’t there, contact the servicer in writing and ask them to correct the posting; mortgage servicers must respond to written error notices under federal rules.
Bing Map Locator: Free Loan and Housing Help Near You
A schedule tells you the math; a counselor can help you decide. Pick what you need and open Bing Maps centered on your location.
Who to Call About Your Loan
Your servicer’s number is on your monthly statement. These free resources help when you need a second opinion.
Free helpOur Verdict
Generate the schedule once, find your current row, and note three dates: when principal overtakes interest, when you reach 80% of your home’s value if you pay PMI, and your payoff date. Then test one small extra payment. For most people, a modest amount added early, clearly labeled as principal, changes the loan more than any other single move.
Questions people still ask
What’s the difference between amortization and depreciation?
Amortization spreads a loan’s repayment, or an intangible asset’s cost, over time. Depreciation spreads the cost of a physical asset like a car or equipment over its useful life.
Does an amortization schedule include property taxes?
No. It covers principal and interest only. Taxes, homeowners insurance and mortgage insurance are often collected through escrow in the same bill, but they’re separate from the schedule.
How much faster will I pay off my loan with extra payments?
It depends on the rate, the balance and when you start. On a $400,000, 30-year loan at 7.18%, $200 a month extra from the start ends the loan about 70 payments sooner. Use the generator for your own loan.
Is a biweekly mortgage worth it?
The benefit comes from making one extra payment a year. You can get the same result yourself, without fees, by adding one-twelfth of your payment to each monthly bill.
Why did my interest go down but my payment stay the same?
That’s amortization working. Your fixed payment stays level while the interest portion shrinks and the principal portion grows each month.
Can I get a schedule from my lender?
Yes. Many lenders show one in your online account or will send it on request. Comparing it with an independent schedule helps you spot posting errors.
How do I calculate mortgage interest for taxes?
Your lender reports interest paid on Form 1098 each year. The yearly view of the generator gives a close estimate for planning, but use the form for your return.
Do student loans follow an amortization schedule?
Standard repayment plans do. Income-driven plans base the payment on income instead, so the balance may fall slowly or not at all in some years.
What happens to the schedule if I miss a payment?
Interest keeps accruing, and late fees may apply. On daily-interest loans more of your next payment goes to interest, and the balance falls more slowly than the schedule shows.
What’s negative amortization?
It happens when payments don’t cover the interest due, so the unpaid interest is added to the balance and the loan grows. It’s rare in standard mortgages today and is something to avoid.
How this page was checked. Mortgage rates come from Freddie Mac’s most recent weekly survey; auto loan figures from Edmunds’ latest quarterly report; the personal loan rate from the Federal Reserve’s consumer credit release. Prepayment penalty limits reflect federal ability-to-repay rules, and PMI thresholds reflect the Homeowners Protection Act. Schedules, charts and examples are our own calculations using standard amortization, cross-checked with Excel’s PMT, IPMT and PPMT functions. Your loan documents and servicer statements are the final word.
This page is independent and isn’t affiliated with any lender. It is general information, not financial advice.
Key sources: Freddie Mac · Federal Reserve · CFPB · Edmunds