Why this works
- This is the single most effective reminder. Most late payments are forgotten invoices, and this one lands before anyone is late — so nobody is embarrassed.
- Re-attach the invoice. The original is often buried in an inbox or never reached the person who pays.
- Ask if they need anything (a PO number, a supplier form). That surfaces blockers before the due date, not after it.
Useful tools for this stage
- Late payment interest calculator — the exact interest and compensation to quote.
- WhatsApp & SMS reminder generator — for clients who ignore email.
- Letter before action generator — when reminders have run out.