PayBirch

Free tool

Late Payment Calculator

Enter an invoice's due date to see exactly how many days overdue it is — free, no account needed.

Only fill this in if you and your client already agreed to a specific rate — this just does the arithmetic on the number you enter. PayBirch never invents a legal or statutory late-fee rate for you.

What counts as a late payment?

An invoice is late the moment it passes its due date without being paid — there's no universal grace period unless you've written one into your payment terms. This calculator compares the due date against today (or an actual payment date, if you enter one) to show exactly how many days that is.

Why PayBirch doesn't calculate legal late fees automatically

Statutory late-payment interest and allowable fees differ by country, by state or province, and by what's actually written in your contract — there's no single correct number PayBirch could apply across every business. The optional field above only multiplies a rate you provide, because you and your client already agreed to it, or you're exploring what a specific rate would come to. It isn't legal or tax advice, and you should check your own contract or a professional if you plan to actually charge a late fee.

What to do once you know an invoice is overdue

  • Send a reminder matched to how overdue it is — friendly within the first few days, firmer after a few weeks
  • Restate the invoice number, amount, and due date — don't make the client dig for it
  • Ask directly for a payment date or confirmation, not just "just a reminder"

PayBirch's free reminder generator writes one for you in seconds, and the reminder schedule generator plans out the whole sequence based on how reliable the client usually is.

Tracking this without checking manually

Checking due dates invoice by invoice doesn't scale past a handful of clients. PayBirch's invoice chasing software tracks every open invoice and tells you exactly who needs a reminder today, while automatic invoice reminders send the right one on schedule — stopping the moment the invoice is marked paid.

FAQ

Late payment calculator, answered

It's the number of days between the invoice's due date and either today (if it's still unpaid) or the payment date you enter. There's no grace period applied unless you account for one yourself in the due date.

No. Statutory late-payment interest and fees vary by country, state, and contract, so PayBirch doesn't invent a number for you. The optional late-fee field below only does simple math on a rate you type in yourself — it's not legal advice.

That depends on what you agreed in your contract or payment terms, and on your local law. If you want to apply a specific late-fee rate, add it to your invoice or payment terms in advance — this tool can estimate the amount once you know the rate, but can't tell you whether it's legally enforceable.

Send a reminder matched to how overdue it is — friendly shortly after the due date, firmer as it drags on. PayBirch's free reminder generator writes one for you, or see invoice reminder email templates for ready-to-use wording.

Yes. PayBirch tracks every invoice's due date and flags exactly which ones need attention each day in the Cashflow Hub, instead of checking manually.

Track overdue invoices and let PayBirch handle the follow-ups

PayBirch flags exactly who's overdue and sends the right reminder automatically. Start your 14-day free trial.

All free tools · Reminder schedule generator · Invoice chasing software