Direct Answer
A personal or business loan amortization schedule shows how each fixed payment splits between interest and principal until the balance hits zero. Use Monthly payment = P * r(1+r)^n / ((1+r)^n - 1). Example: $15,000 at 11% for 5 years → about $326/month and ~$4,568 total interest. Build your full table with the Amortization Calculator or Loan Repayment Schedule.
Last verified on: July 13, 2026
Editorial note: Examples use fixed, fully amortizing loans. Variable rates, fees, interest-only periods, and balloons change the schedule. This is educational content, not lending advice.
Research method: Standard amortization formula (same structure used in CFPB loan illustrations) with three modeled scenarios. Verified July 13, 2026.
What amortization means for personal and business loans
Amortization is paying a loan down with regular payments that cover accrued interest first, then reduce principal. A schedule lists every period so you can see:
- Interest charged that month
- Principal applied that month
- Remaining balance
- Total interest over the full term
Personal installment loans and fixed-rate business term loans use the same engine as mortgages. Credit cards and many HELOCs behave differently because the balance can revolve.
For the underlying formula deep dive, see Amortization formula explained.
The formula (with inputs labeled)
Monthly payment (M) = P * [r(1 + r)^n] / [(1 + r)^n - 1]| Symbol | Meaning | Example |
|---|---|---|
| P | Starting principal | $15,000 |
| Annual rate | Stated annual percentage rate (APR) before dividing | 11% |
| r | Monthly rate = annual ÷ 12 | 0.11 ÷ 12 = 0.0091667 |
| n | Number of monthly payments | 5 * 12 = 60 |
| M | Level monthly payment | ~$326.14 |
Each month:
- Interest = current balance * r
- Principal = M - interest
- New balance = prior balance - principal
Three worked examples (different sizes and rates)
Example 1 — Personal loan: $15,000 at 11% for 5 years
| Metric | Value |
|---|---|
| Monthly payment | $326.14 |
| Total of 60 payments | $19,568 |
| Total interest | ~$4,568 |
Selected rows from the schedule:
| Month | Interest | Principal | Balance after payment |
|---|---|---|---|
| 1 | $137.50 | $188.64 | $14,811.36 |
| 2 | $135.77 | $190.37 | $14,621.00 |
| 24 | $93.45 | $232.69 | $9,961.79 |
| 60 | $2.96 | $323.17 | $0.00 |
Variation insight: By month 24, principal already exceeds interest each month. Extra payments in year one cut the ~$4,568 interest bill the most.
Example 2 — Shorter, higher-rate personal loan: $8,000 at 14% for 3 years
| Metric | Value |
|---|---|
| Monthly payment | $273.42 |
| Total of 36 payments | $9,843 |
| Total interest | ~$1,843 |
Compared with Example 1:
| Loan | Amount | Rate | Term | Payment | Total interest |
|---|---|---|---|---|---|
| Example 1 | $15,000 | 11% | 5 years | $326 | ~$4,568 |
| Example 2 | $8,000 | 14% | 3 years | $273 | ~$1,843 |
Variation insight: The smaller loan costs less total interest even at a higher rate because the term is short and principal is lower. When you shop personal loans, compare total interest, not only APR or monthly payment.
Example 3 — Business term loan: $75,000 at 9.5% for 7 years
| Metric | Value |
|---|---|
| Monthly payment | $1,225.80 |
| Total of 84 payments | $102,967 |
| Total interest | ~$27,967 |
Selected rows:
| Month | Interest | Principal | Balance after payment |
|---|---|---|---|
| 1 | $593.75 | $632.05 | $74,367.95 |
| 12 | $536.48 | $689.32 | $67,076.30 |
| 36 | $392.86 | $832.94 | $48,791.62 |
| 84 | $9.63 | $1,216.17 | $0.00 |
Variation insight: Business loans often carry larger balances, so interest dollars stay high for years even when the APR looks “reasonable.” A one-year interest-only period (common on some commercial notes) would keep the balance near $75,000 until amortization starts — pushing total interest higher than this fully amortizing case.
How to build your own schedule in minutes
- Open the Amortization Calculator.
- Enter loan amount, annual rate, and term in years (or months if your note is odd-length).
- Review the month-by-month table.
- Export CSV for Excel/Sheets or print a PDF.
- Optional: add an extra monthly principal amount and compare payoff date and interest.
For spreadsheet formulas from scratch, use Build an amortization schedule in Excel.
Personal vs business vs other loan types
| Loan type | Typical amortizing? | Watch for |
|---|---|---|
| Personal installment | Yes, fixed payment | Origination fees, prepayment clauses |
| Business term loan | Often yes | Interest-only start, balloons, covenants |
| Business line of credit | Revolving | No single payoff date until you stop draws |
| Auto loan | Yes | Depreciation vs balance (negative equity) |
| Student loan (standard) | Yes | Income-Driven Repayment (IDR) plans can differ — see student loan schedule |
| Credit card | Minimums only | Revolving; use credit card payoff calculator |
Extra payments: quick impact check
On Example 1 ($15,000 at 11% for 5 years), adding $50/month to principal:
- Shortens the term by roughly 8-9 months
- Cuts total interest by roughly $600-700 (order-of-magnitude; confirm in the calculator)
Always tell the lender to apply extras to principal. Related guide: Extra payments amortization schedule.
Related Reading
- Amortization formula explained — deeper math on each variable
- What is amortization? — plain-English overview
- Extra payments amortization schedule — how extras change the table
- Student loan amortization schedule — fixed vs income-driven plans
- Boat & RV loan amortization guide — specialty vehicle schedules
- Amortization Calculator — build and export your table
Official and supporting sources
Frequently Asked Questions
What is a personal loan amortization schedule?
A personal loan amortization schedule is a month-by-month table showing how each fixed payment splits between interest and principal until the balance reaches zero. Early payments are interest-heavy because the balance is largest; later payments are mostly principal. The same math powers business term loans, auto loans, and mortgages — only the rate, term, and fees differ.
How do I calculate a business loan amortization schedule?
Use the standard fixed-payment formula: monthly payment = P × r(1+r)^n / ((1+r)^n − 1), where P is the loan amount, r is the monthly interest rate, and n is the number of months. For each month, interest = balance × r, and principal = payment − interest. Enter your amount, rate, and term in the Amortization Calculator to export a full schedule to CSV or PDF.
Why is my first personal loan payment mostly interest?
Interest accrues on the full outstanding balance. On a $15,000 loan at 11%, the first month accrues about $137.50 of interest, so a $326 payment applies roughly $189 to principal. As the balance falls, monthly interest falls and more of each payment reduces principal. That pattern is normal amortization, not a lender error.
Can I pay off a personal or business loan early?
Most personal loans allow prepayment; some charge a prepayment penalty, so read the note. Extra principal reduces future interest immediately if the lender applies it to principal rather than advancing your due date. Business term loans vary more — SBA and bank notes may have prepayment formulas in the first years. Model extra payments in the Amortization Calculator before you commit cash.
Is a business loan amortization schedule different from a personal loan?
The amortization math is the same for fixed-rate, fully amortizing term loans. Business loans often have higher balances, different rates, fees, or interest-only periods at the start. Interest-only months do not reduce principal, so the later amortizing schedule looks steeper. Always confirm whether your note is fully amortizing, interest-only then balloon, or revolving like a line of credit.
Personal loan vs credit card — which amortizes better?
A fixed personal loan amortizes to a clear payoff date if you make every payment. Credit cards are revolving: paying only the minimum can keep the balance open for years. If you consolidate card debt into a fixed personal loan, you trade revolving flexibility for a defined schedule — usually lower interest if your credit qualifies. Compare total interest with a credit card payoff calculator and an amortization schedule side by side.
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