Late Payment Fee Calculator
Calculate the late fee and total due on an overdue invoice.
About the Late Payment Fee Calculator
Most invoices and contracts specify a late payment charge — commonly 1.5-2% per month — but almost nobody actually calculates what that amounts to on a specific overdue amount for a specific number of days late. This calculator does that arithmetic instantly: enter the invoice amount, the agreed monthly rate, and days overdue, and get the exact late fee and total now due.
The calculation converts your monthly rate to a daily rate (monthly rate ÷ 30) and applies it per day overdue — a simple, defensible method that matches how most late-fee clauses are actually worded. This makes the number concrete rather than abstract when you're following up on late payment, which strengthens a payment reminder considerably: "the late fee is currently ₹1,167 and grows daily" lands harder than a vague mention of penalties.
Before charging a late fee, confirm your invoice or contract actually specifies one — charging a fee that wasn't agreed upfront is legally shaky and damages the relationship. If you haven't been including a late-fee clause, add one to future invoices and contracts so this calculator has real teeth going forward.
Recalculate as the overdue period grows rather than quoting a stale figure from the first reminder — the fee compounds daily under most clause wordings, so a number quoted three weeks ago understates what's actually owed today. Keeping the figure current also signals to the customer that you're tracking the account closely.
Frequently asked questions
- What late fee rate is standard?
- 1.5-2% per month is common in Indian B2B invoicing and contracts, though it varies by industry and negotiating power. Whatever rate you use, it should be explicitly stated in your invoice terms or contract before you attempt to charge it.
- Can I charge a late fee if it wasn't mentioned on the invoice?
- Legally and practically, no — a late fee needs to be agreed in advance (on the invoice, in a contract, or in your standard terms) to be enforceable. Add a late-fee clause to future invoices if you don't already.
- How is the daily rate calculated from a monthly rate?
- Monthly rate ÷ 30 gives a daily rate, which is then applied to the invoice amount for the exact number of days overdue — a simple, commonly used method for pro-rating monthly late-fee clauses.
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