Chasing an unpaid invoice without losing the client

Overdue invoices are usually an administration problem, not a hostility problem. The sequence below assumes good faith first and escalates on a schedule rather than a mood.

Short answer

• Remind once before the due date and once after; do not apologise for either.
• Escalate on a fixed schedule, not when you get annoyed.
• Name the consequence once, in writing, then follow through.
• Keep every message short, factual and free of accusation.

The four steps

• Two days before the due date — a one-line reminder with the invoice attached and the amount restated.
• Three days after — the same message, plus a question: 'has this reached the right person for payment?' This catches the routing failure, which is the most common cause.
• Ten days after — state the late fee, restate the pause on new work, and ask for a payment date rather than an apology.
• Twenty-one days after — a formal final notice, with the escalation route named (collections, or the small-claims route that applies where you are).

Wording that keeps the relationship

• Use the passive voice for the problem and the active for the action: 'this invoice is still showing unpaid' rather than 'you have not paid'.
• Ask for a date, not a reason. A date is actionable; a reason is a conversation.
• Never send more than one message a week, and never send at night.

When it is not an administration problem

If the third message produces neither a date nor a dispute, stop negotiating privately. Withhold the remaining deliverables if any are outstanding, confirm in writing that the work is complete and unpaid, and move to the formal route. Continuing to work for a non-paying client is the expensive mistake, not the unpaid invoice.