Invoice Not Paid? Here's Exactly What to Do (Step by Step)

Don't Panic — But Do Act Quickly

Most unpaid invoices are not deliberate non-payment. They're lost emails, forgotten due dates, busy accounts payable departments, or cash flow problems the client hasn't told you about. A systematic follow-up process resolves the majority of cases.

The key rule: act sooner than feels comfortable. Every week you wait makes collection harder.

Step 1: Check the Basics First

Before chasing, confirm:

Did you send the invoice to the right email address?

Did you include your bank details?

Is the due date actually past (not just close)?

Has the client paid and the payment just hasn't cleared?

A quick check prevents an embarrassing chase for an invoice that was already paid or never received.

Step 2: Friendly Reminder (1–3 Days Overdue)

Send a polite, non-accusatory reminder. Assume oversight.

Email template:

Subject: Invoice INV-2025-047 — Gentle Reminder

Hi [Name],

I wanted to follow up on invoice INV-2025-047 for $[amount], which was due on [date]. I've attached a copy in case it's been missed.

Please let me know if you have any questions or if there's anything I can help with to process the payment.

Thanks,

[Your name]

Step 3: Direct Follow-Up (7–14 Days Overdue)

If no response, escalate tone slightly. Still professional.

Email template:

Subject: Overdue: Invoice INV-2025-047 — [Your Business Name]

Hi [Name],

I'm following up again on invoice INV-2025-047 for $[amount], now [X] days overdue. This invoice was due on [date].

Could you please let me know the expected payment date, or confirm if there is an issue I should be aware of?

I've attached the invoice again for reference.

[Your name]

Step 4: Pick Up the Phone (14–21 Days Overdue)

Email is easy to ignore. A phone call is not. Call the accounts payable department directly — not your project contact.

Be calm and factual: "I'm calling about invoice INV-2025-047 for $[amount] which has been outstanding since [date]. I wanted to check when we can expect payment."

Note the response: if they give you a date, follow up if that date passes without payment.

Step 5: Formal Written Notice (30+ Days Overdue)

Send a formal demand letter via email (with read receipt) and, for significant amounts, by post as well.

State clearly:

The invoice number, amount, and due date

The number of days overdue

That you require payment within 7 days

That you will pursue further action if payment is not received

Mention any late payment interest that applies under your contract or local law.

Step 6: Escalation Options

If payment still doesn't arrive:

Debt collection agency: Works on a commission basis (typically 10–25% of the recovered amount). Effective for B2B debts. Some agencies send a single letter that resolves 50–60% of cases.

Solicitor's letter: A letter from a lawyer carries weight. Often resolves disputes without court action.

Small claims court: For smaller amounts, small claims court is designed for individuals and businesses to pursue debts without needing a lawyer. Filing fees are modest; if you win, court costs are added to the debt.

Suspend services: If you have an ongoing relationship, suspend services until the overdue amount is settled. Make this clear in your terms of business.

Preventing Future Late Payments

Request a deposit from new clients

Use shorter payment terms (Net 14 instead of Net 30)

Add a late payment clause to your invoices

Follow up on the due date, not after it

Use invoicing software that flags overdue invoices automatically

Quotation Expert shows every overdue invoice on your dashboard with the number of days outstanding — so you see the problem immediately rather than discovering it weeks later.