Example 1
- Amount: 200,000
- Rate: 7.5%
- Term: 240 months (20 years)
Highest first payment
Last ≈ principal slice + small interest
Interest often below annuity
Higher start burden, faster early principal reduction.
Decreasing instalment calculator
Type the loan amount, the nominal annual interest rate, and the term in months. The principal slice stays flat; interest falls with the balance. At 200,000, 7.5%, and 240 months the first payment is 2,083.33 and the principal slice is 833.33.
Flat principal slice plus interest on the balance. Compare with an annuity, the equal installment, in the options. Full table: amortization schedule. A sketch, not a full schedule.
Results
Loan amount, Nominal annual interest rate (%), Term (months) and First payment date (optional). The result shows up here.
How results are calculated
A decreasing installment splits the loan amount into equal principal slices and charges interest on the current balance. At 200,000, 7.5%, and 240 months the slice is 833.33, the first payment is 2,083.33, and the last is about 838.54. Total interest in this model is 150,625. An annuity, the equal installment, at the same inputs is 1,611.19, with interest near 186,685. The decreasing start is higher; total interest is lower.
People compare this system with a level payment when the first month has to fit the budget. You type the term in months, not years: 20 years is 240. The calculator does not build a full lender table and does not change the rate mid-term. Compare with equal (annuity) instalment, when checked, shows the first-payment and interest gap at the same three numbers.
The fields are Loan amount, Nominal annual interest rate (%), and Term (months). First payment date is optional. Additional options hold an Upfront / arrangement fee, a Monthly fee, and an Extra monthly overpayment. The extra goes to principal after the contractual P divided by n slice and can shorten the count of payments. All-in is the sum of installments plus the upfront fee plus the monthly fee times the actual number of payments.
At 50,000, 11%, and 60 months the first payment is 1,291.67, the last about 840.97, interest 13,979.17. A 500 upfront fee lifts all-in to 64,479.17. The annuity at those inputs is 1,087.12: a lower start, higher interest. At 300,000, 6.5%, 300 months, a 15 fee and a 200 extra, the first payment with extra is 2,825 and the term shrinks by 50 months.
Header currency only labels the amounts. A comma and a period in 7.5 mean the same rate. The calculator waits for amount, rate, and a positive term in months. This is a fixed-rate teaching model, not a full schedule and not a credit decision.
Type 200,000, 7.5, and 240, leave the comparison on, click Calculate, and check 2,083.33 next to 1,611.19. Then try 50,000, 11, 60, and a 500 fee to see 1,291.67 and all-in 64,479.17.
How to use
- Type Loan amount, for example 200,000, Nominal annual interest rate (%), for example 7.5, and Term (months), for example 240.
- Optionally set First payment date and, under Additional options, an Upfront / arrangement fee, a Monthly fee, or an Extra monthly overpayment.
- Leave Compare with equal (annuity) instalment checked if you want the first-payment and interest gap at the same principal.
- Click Calculate. At 200,000, 7.5%, and 240 months the first payment is 2,083.33, the slice 833.33, interest 150,625.
- For a month-by-month table, open the amortization schedule. The classic equal payment is on the loan installment page.
Declining payment: flat principal, falling interest
The principal slice stays flat; interest falls with the balance. At 200000, 7.5%, and 240 months the first payment is 2083.33 and the principal slice is 833.33.
- principal
- Amount / months in this calculator. 200000 / 240 ≈ 833.33, first payment 2083.33 at 7.5%.
- annuity
- Optional compare with the equal installment. Compare with equal (annuity) instalment. First-payment difference is declining minus equal.
- All-in
- Installments plus fees. 50000, 11%, 60 months and a 500 fee: all-in = installments + 500.
Examples
Example 2
- Amount: 50,000
- 11%, 60 months
- Upfront fee: 500
All-in = instalments + 500
Compare first payment vs annuity
Shorter term - payment drop is easier to see.
Example 3
- Amount: 300,000
- 6.5%, 300 months
- Fee 15/mo, extra +200
Overpayment shortens term
Fees raise all-in
Simplified overpayment - details in the amortization schedule.
Example 4
- 50,000
- 11%
- 60 months
First payment 1,291.67
What is the first decreasing payment on 50,000 at 11% over 60 months? First payment 1,291.67.
Example 5
- 80,000
- 8%
- 120 months
First payment 1,200.00
What is the first decreasing payment on 80,000 at 8% over 120 months? First payment 1,200.00.
Related calculators
FAQ
What is the first payment on 200,000 at 7.5% for 240 months?
2,083.33. Principal slice 200,000 / 240 = 833.33, opening interest 1,250. Last payment about 838.54. Total interest 150,625.
What is the annuity, the equal installment, at the same 200,000?
1,611.19. Annuity interest is about 186,685. The decreasing start is higher and the interest total is lower.
What is the first payment on 50,000 at 11% for 60 months?
1,291.67. Last about 840.97, interest 13,979.17. A 500 fee makes all-in 64,479.17. The annuity at those inputs is 1,087.12.
Do I type 20 years as 20?
No. The field is Term (months). Twenty years is 240. Five years is 60.
How does Extra monthly overpayment work?
The contractual slice stays amount divided by n. Extra comes off the balance and can shorten the term. At 300,000, 6.5%, 300, and extra 200, you save 50 months.
Does the 15 fee sit inside the 2,083.33 first payment?
No. The first payment is principal plus interest plus any extra. The monthly fee and the upfront fee go into all-in.
Where is the full table?
On the amortization schedule. Here you see first, last, and average payment, interest, and the annuity comparison.
Does a comma in 7.5 work?
Yes. 7,5 and 7.5 are the same rate. Header currency only labels the result.
Is this a credit decision?
No. It is a fixed-rate sketch. An offer may round differently and may change the rate later.
How is this different from an 833.33 equal split?
833.33 with no interest lives on the equal-split page. Here the same slice plus interest on the balance makes the first 200,000 payment 2,083.33.
Knowledge sources
A decreasing installment is a flat principal slice plus interest on the balance. This is a sketch, not a full schedule.
Page updated in 2026.