Invoice Late Payment Calculator

Calculate interest owed on overdue invoices and generate a follow-up email.

Invoice Amount ($)

Annual Interest Rate (%)

Invoice Due Date

Today's Date

410 days overdue

$5,000.00

Original Invoice

$1,010.96

Interest Owed

$6,010.96

Total Now Owed

Calculated at 18% p.a. (0.0493%/day) × 410 days

Follow-up Email Template

Subject: Overdue Invoice – Payment Required

Dear [Client Name],

I hope this message finds you well. I'm writing to follow up on invoice #[INVOICE NUMBER] for $5,000.00, which was due on January 15, 2025.

As of today, this invoice is 410 days overdue. As per our agreed payment terms, a late payment interest of 18% per annum has been applied, bringing the total now owed to $6,010.96 (including $1,010.96 in interest).

Please arrange payment at your earliest convenience. If payment has already been sent, please disregard this notice and share confirmation so I can update our records.

If you have any questions or would like to discuss payment arrangements, please don't hesitate to reach out.

Thank you for your prompt attention to this matter.

Best regards,
[Your Name]
[Your Business]
[Phone / Email]

Replace the bracketed placeholders before sending.