Enter your invoice amount, due date, and fee rate to see exactly how many days overdue it is, the late fee, and the total amount owed. Free, and no signup needed.
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Once the late fee is paid, keep every invoice, reminder, and payment in one place.
Chasing an overdue invoice is awkward enough without also doing the math by hand. This calculator takes your invoice amount, due date, and fee rate and instantly shows how many days overdue the payment is, exactly what the late fee comes to, and the new total your client owes, so the number you send them is correct the first time.
Most businesses charge a late fee one of two ways: a flat one-time amount, or a percentage of the invoice that accrues for each month it stays unpaid.
Flat fee: Late Fee = Flat Amount (applied once the invoice is overdue) Percentage per month: Late Fee = Invoice Amount x (Monthly Rate / 100) x (Days Overdue / 30)Pick whichever method matches what you actually put in your contract or invoice terms. The calculator switches the input label automatically depending on which type you choose.
Enter the invoice amount, the date it was due, and, if you want to check the fee as of a date other than today, an as-of date. Choose whether your late fee is a flat dollar amount or a percentage that accrues monthly, enter the rate, and the days overdue, late fee, and total amount owed update as you type. Click "Show suggested reminder message" for a ready-to-send, polite reminder built from your own numbers.
Yes. A late fee is far easier to collect, and far less likely to be disputed, when it was disclosed in writing before the work started, whether that is in a contract, a signed estimate, or the payment terms printed on the original invoice. Applying a fee a client was never told about tends to create a billing dispute instead of a payment.
Late fee rules are not the same everywhere. Some states cap the annual rate a business can charge before it is treated as an interest charge subject to lending or usury laws, and the rules differ for B2B versus consumer invoices. Check your own state's specific requirements, or ask an attorney, before finalizing the rate you put in your contracts and invoices.
This calculator provides estimates for planning purposes. Actual late fee terms are set by the agreement between you and your client, and may be subject to state law.
Set your payment terms once in Billbooks and send professional invoices, reminders, and receipts from one account.
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Not sure the invoice is actually overdue yet? The invoice due date calculator works out the exact date from your terms. Wondering what the chasing itself costs you? The manual invoicing cost calculator puts a number on it.
Every trade bills differently. See how Billbooks fits yours:
Several small jobs a day, labor and materials on one invoice.
Deposits, materials markup, and job line items, handled right.
Keep the diagnostic fee separate from the repair cost.
Progress billing, retainage, and change orders.
Labor and parts priced right, plus a fair shop supply fee.
See how Billbooks fits your specific trade or business.
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