Transparent by design

How KindlyDue drafts a follow-up.

No opaque score and no claim that software understands your client better than you do. The founding edition uses a small, inspectable set of rules.

Inputs

The tool uses the client name, invoice number, amount, due date, optional context, optional payment link, whether a reminder was already sent, and the wording choices you make. Those choices include tone, situation, message length, requested response, and an optional custom sentence. It does not read the underlying invoice or verify that the amount is owed.

Tone recommendation

• Friendly: not yet due through seven days overdue.
• Clear: eight through 21 days overdue when no prior reminder is recorded.
• Firm: more than 21 days overdue, or after a previous reminder later in the cycle.

These are communication defaults, not legal thresholds. The tone selector always lets you override them.

Wording controls

The editor can combine:

• five voices: warm, friendly, clear, firm, and formal;
• six situations: general, first reminder, repeat reminder, missed payment promise, possible admin issue, and payment-plan discussion;
• three lengths: brief, standard, and detailed;
• five requested responses: confirm a payment date, pay now, confirm receipt, explain an issue, or propose a schedule.

The selected situation is treated as a fact supplied by the user. For example, the tool only mentions a missed payment promise when that situation is selected.

Message boundaries

Generated messages are designed to:

• identify the invoice, amount, and original due date;
• make the requested next step explicit;
• avoid shaming, threats, or invented urgency;
• avoid adding interest, fees, or legal claims.

Follow-up rhythm

The calendar starts on the due date for an upcoming invoice or on the selected “as of” date for an overdue one. It then suggests checks at three, seven, and 14 days. This is an organizational aid; contracts, disputes, client promises, and local law may justify a different schedule.

Why the problem matters

The2026 QuickBooks Small Business Late Payments Reportsays 59% of surveyed businesses had invoices overdue by 30 days or more, and businesses with unpaid invoices were owed $17,700 on average. This is vendor research, not a universal estimate, but it provides current evidence that the problem is broad and costly.

Versioning

Current drafting methodology: 1.1.0. Material changes should be documented in the repository changelog and covered by automated tests.