Tools
Outstanding balance & partial payment calculator (2026)
Enter the invoice total, payments received, and any credits to see the balance due, percent paid, and whether the invoice is overdue. Due date calculator · Late payment calculator
Updated May 22, 2026
Calculator
Balance due
$2,500.00
Collected
50%
Original total
$5,000.00
Balance due: $2,500.00
10 days overdue (due Sun, May 24, 2026). 50% of $5,000.00 collected.
Estimate late fees with the late payment calculator. Then use reminder templates for the remaining $2,500.00.
Partial payments and reminder emails
When a client pays part of an invoice, your reminder should reference the remaining balance and due date, not the original total.
Use this calculator before you send a follow-up, then pick a template that matches how overdue the invoice is.
Outstanding balance calculator FAQ
- How do I calculate outstanding balance on an invoice?
- Subtract payments received and any credit notes from the invoice total. The result is the balance due. Compare the due date to today to see if it is overdue.
- What if the client paid half?
- Enter the full invoice amount in total, then enter the partial payment in payments received. The calculator shows the remaining balance and how many days past due it is.
- Should I send a reminder on a partial payment?
- Yes if the balance is still due and past your terms. Acknowledge what they paid, state the remaining amount, and include the due date or days overdue.
- Is this balance due calculator free?
- Yes. It works in the browser with no account. Pair it with late fee and email templates, or automate reminders in NowPaid.