Money Math
Payment Over Time Calculator
Build a complete payment schedule for a settlement paid with up-front payments and installments.
How it works
When a settlement is paid over time rather than in one check, the structure has more moving parts than people expect: up-front payments, installment amounts, frequency, and whether the unpaid balance bears interest. This calculator builds the complete payment schedule.
Enter the total settlement, any up-front payments (each with its own label — “at signing,” “30 days,” whatever fits the deal), and the installment terms. The calculator works in either direction: fix the number of payments and it computes the payment amount, or fix the payment amount and it computes how many payments are needed. Frequency can be monthly, quarterly, or any custom interval in days.
If interest applies, the tool uses standard amortization — each level payment contains a declining interest component and a growing principal component, exactly like a loan. The schedule shows every payment broken into principal, interest, and remaining balance, and the summary totals what the payor ultimately pays.
Worked example
A $120,000 settlement with $20,000 at signing leaves $100,000 to amortize. Paid over 12 monthly installments at 6% interest, each payment is $8,606.64, total interest is about $3,279.71, and the payor's all-in cost is $123,279.71. At 0% the same structure is twelve flat payments of $8,333.33.
When to use it
Use it while negotiating structure — it answers “what does $10,000 a month for two years actually total?” instantly — and when drafting, because the exported schedule can go straight into the settlement agreement as an exhibit.
Frequently asked questions
Should a settlement paid over time include interest?
That's a negotiation point. Interest compensates the plaintiff for waiting and for credit risk; payors resist it. Even at modest rates it adds up — this tool shows both sides exactly what any rate costs, which usually shortens that part of the conversation.
How is the installment payment calculated with interest?
With the standard amortization formula used for loans: a level payment such that interest accrues on the unpaid balance each period and the balance reaches zero on the final payment. Early payments are interest-heavy; later payments are principal-heavy. The schedule shows the split for every payment.
What happens if the payment amount is too small to cover the interest?
The balance would grow forever — so the calculator warns you instead of producing an endless schedule. Increase the payment or lower the rate.
Can I model an up-front payment plus installments?
Yes — that's the typical structure. Up-front payments are applied to the balance before installments begin, and you can list several with different labels and timing.