Invoice Late Fee Calculator
Enter your invoice amount, due date, and fee structure to see exactly what you're owed today — plus 30/60/90-day projections and copy-paste contract language.
Compound interest
Compounds monthly
APR: 18.00% — Most US states cap commercial late fees at 18–24% APR. Late fees are only enforceable if stated in the original contract.
Fee milestones (after due date)
Invoice Summary
Legal notes:
- Only enforceable if in original contract
- Most states cap at 1.5–2%/month (18–24% APR)
- CA, TX, NY have additional usury restrictions
- Grace periods are common practice (5–15 days)
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