Invoice math
Rules for turning an invoice's age and balance into the right action.
Aging buckets
Measure age from the invoice due date (not issue date).
| Bucket | Age (days past due) | Reminder tier |
|---|
| Upcoming | −7 to 0 | Courtesy notice |
| Just overdue | 1 to 7 | First reminder |
| Overdue | 8 to 30 | Second reminder |
| Seriously late | 31 to 60 | Final notice |
| Delinquent | 61+ | Hold for human |
Reminder tiers
- Courtesy notice — friendly heads-up that payment is due soon. No pressure.
- First reminder — a polite nudge with the amount, due date, and pay link.
- Second reminder — firmer; restate the balance and how many days overdue.
- Final notice — clear consequence framing; still professional.
- Hold for human — do not send. Surface in the summary for a person.
Dunning cadence
- Send at most one reminder per invoice per run, and never two reminders to
the same invoice within 72 hours — check the last-sent log first.
- Escalate a tier only when the invoice crosses into the next bucket, not on
every run.
- Once an invoice is paid, stop immediately and note it in the summary.
Stop-for-human triggers
Regardless of bucket, do not send and hand off to a person when the invoice
is:
- over the approval threshold for the account,
- flagged disputed, or
- marked for collections / legal.