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Last updated: February 19, 2026

Invoice Email: Overdue Invoice Reminder: Templates + Subject Lines

Stop letting unpaid invoices drain your cash flow and sanity. Master the art of the strategic reminder that gets paid without burning bridges.

On this page

• Quick template (short)
• Formal version
• Friendly version
• Firm version
• Subject lines
• Tips
• FAQ
• Personalized generator

Quick Template (Short)

Copy

Hi [[NAME]], this is a reminder that invoice [[REFERENCE]] is now overdue. Please arrange payment today to avoid late fees. Thanks, [[YOUR_NAME]].

Formal Version

Copy

Dear [[NAME]],

This correspondence serves as a formal notice that invoice [[REFERENCE]], originally due on [Date], is now past due. We kindly request immediate settlement to maintain your account in good standing.

For your convenience, the invoice is attached again. Please remit payment via the original method.

Sincerely,
[[YOUR_NAME]]

Friendly Version

Copy

Hey [[NAME]], hope you're having a good week! Just circling back on invoice [[REFERENCE]]—it seems it slipped through the cracks. No rush, but could you please process it when you have a moment? Let me know if you need anything from me! Best, [[YOUR_NAME]]

Firm Version

Copy

[[NAME]],

Despite our previous reminder on [Date of last contact], invoice [[REFERENCE]] remains unpaid. This is your final notice before we consider further collection action.

Payment is required within 5 business days. Contact us immediately to discuss a payment plan if necessary.

[[YOUR_NAME]]

Subject Lines (Pick one)

• Action Required: Invoice [[REFERENCE]] is Overdue
• Following Up: Unpaid Invoice [[REFERENCE]] from [Your Company]
• Urgent: Your Account [[REFERENCE]] is Past Due

Tips

• Always re-attach the original invoice PDF in the reminder email.
• Mention the specific late fee or interest policy from your contract.
• Send reminders from a monitored, real human email address, not a no-reply box.

Related templates

More templates in the same category:

• How to Write Invoice Email: Send Invoice Again (With Examples)
• How to Write Invoice Email: Request Payment Status Update (With Examples)
• Invoice Email: Send Invoice Again — Short, Formal, Friendly, Firm
• Invoice Email: Send Invoice Again: Templates + Subject Lines
• How to Write Invoice Email: Send Invoice Again (With Examples)

FAQ

Q: What is the best day of the week to send an overdue invoice reminder?
A: Tuesday or Wednesday morning is ideal, avoiding Monday inbox clutter and Friday's winding-down focus.

Q: Should I include the original due date in the reminder email?
A: Yes. Stating 'Originally due on [Date]' provides clear, indisputable context and shows professionalism.

Personalized Generator (Fill & Copy)

Fill in the fields to generate a ready-to-send invoice email. Example Invoice: Invoice #INV-7712.