Late payment reminder text and WhatsApp messages

Texts get read in minutes and answered the same day. Twelve short reminders you can send as they are.

3 min read · Updated Nov 3, 2026

Key takeaways

Keep it under 300 characters: name, business, invoice, amount, link.
Send between 9am and 6pm in their time zone, never on Sunday.
WhatsApp needs an approved template for the first message after 24 hours of silence; a plain text doesn't.
One text per rung. If a text gets no reply in three days, move to email, then call.

Why texts work

A payment reminder by email competes with 80 other emails. A text competes with nothing. Open rates are near total, and because a text reads as personal, replies come back fast: "paying now", "Friday", "wrong email, send it to accounts@".

The cost of that intimacy is that a text has to be short, polite and clearly from a business the customer knows.

Before it's due

Hi Lisa, Mike at Ridgeline Remodeling. Heads-up: invoice #2207 ($2,100) is due Friday. Pay here any time: [link]. Thanks!

The day after

Hi Lisa, Mike at Ridgeline. Invoice #2207 for $2,100 was due yesterday. In case it got lost: [link]. Thank you!

Hi Lisa! Hope the kitchen's great. Quick nudge on invoice #2207, $2,100, due Oct 15. Link: [link]. Mike, Ridgeline Remodeling

About a week late

Hi Lisa, checking in on invoice #2207 ($2,100, due Oct 15). Is anything holding it up? Happy to help. Link: [link]. Mike, Ridgeline

Hi Lisa, invoice #2207 ($2,100) is a week past due and I haven't heard back. Could you let me know a date? Pay link: [link]. Mike, Ridgeline Remodeling

Two weeks late

Hi Lisa, invoice #2207 ($2,100) is now two weeks overdue. Please pay by Friday or reply with a date. If something's wrong with the work, tell me and I'll fix it. Mike

Final reminder

Hi Lisa, last reminder on invoice #2207 ($2,100, due Oct 15). Please pay by [date] or reply with a plan; otherwise I'll need to decide next steps. I'd rather sort it with you. Mike, Ridgeline

Replies and thank-yous

Thanks Lisa, Friday works. I'll look out for it. Mike

Thanks for the $1,000, Lisa. That leaves $1,100 on #2207. Does Nov 8 work for the rest? Mike

Got it, thank you Lisa! Receipt on its way. Great working with you. Mike, Ridgeline

In Spanish

Hola Dana, le escribe Mike de Ridgeline Remodeling. La factura #2210 por $975 venció ayer. Por si se perdió: [link]. ¡Gracias!

Hola Dana, último recordatorio de la factura #2210 ($975). ¿Podría pagar antes del viernes o indicarme una fecha? Si hay algún problema, dígame y lo resolvemos. Mike

Texting rules worth knowing

In the US, business texts need the customer's prior consent. Someone who gave you their mobile number for the job and has texted you about it has consented to texts about that job; a stranger from a bought list has not.
Include your business name in every message. An unsigned "you owe $2,100" gets reported as spam.
Give them a way to say stop, and honour it.
Don't text before 8am or after 9pm their time.
WhatsApp: a business can message freely for 24 hours after the customer's last message. After that, the first message must be a pre-approved template. Invoice AI's templates are approved for this.

Sending them without typing them

Invoice AI sends these exact messages, in your name, from your business number, by WhatsApp or text depending on what the customer has, with the email and the polite call on the days in between. You type "Lisa Park owes $2,100, 12 days late" once.

Questions people ask

Can I text a customer about an unpaid invoice?

Yes, if they gave you their mobile number for the job. Keep it short, sign it with your business name, and send during business hours.

WhatsApp or SMS for payment reminders?

WhatsApp where the customer uses it (most of the world, and a growing share of the US); SMS otherwise. WhatsApp shows read receipts and allows a payment button.

How long should a payment reminder text be?

Under 300 characters. Name, business, invoice number, amount and a link. Anything longer gets skimmed.

What time should I send a payment reminder text?

Between 9am and 6pm on a weekday in the customer's time zone. Tuesday to Thursday mornings get the fastest replies.