How soon after the due date should you send the first reminder?

The next working day, once you have checked that the money has not already arrived. Waiting a week to be polite does not make you more likely to be paid; it just moves the whole conversation a week later, and by then the invoice has left the top of the pile. Sending on day one, in a tone that assumes an oversight, costs you nothing with a good customer and buys you six days with a bad one.

Should the first reminder mention late fees?

No. A late fee threat on day one is a consequence attached to something that might be a holiday or an approval queue, and you have nothing to escalate to afterwards. If your terms carry interest, the place to state it is the two-week email, after a neutral reminder has been ignored. Stating it once, calmly, at that point carries far more weight than stating it immediately.

Invoice due today reminder — day 1 overdue email template

One day past due is almost never a refusal. This email is written as if the delay is procedural, because it usually is.

Day 1 overdue
Friendly tone

The email

Subject

Invoice [Invoice number] was due yesterday

Body

Hi [Customer name],

Invoice [Invoice number] for [Amount] was due on [Due date] and I do not have it on my side yet.

I expect it is just sitting in a queue somewhere. If it is, no need to reply — I will keep an eye out for it. If something is holding it up, tell me what and I will sort it out.

Invoice attached again for convenience.

Thanks,
[Your name]
[Your business]

Fill in before you send

[Customer name]
[Invoice number]
[Amount]
[Due date]
[Your name]
[Your business]

When to send this

The working day after the due date, to a customer with a good record.
When you have already checked your bank, your payment processor and your accounting software, and the money genuinely is not there.
When you would rather hear about a problem now than discover it in three weeks.

When not to send this

The wrong reminder at the wrong moment costs more than no reminder at all.

Before you have checked every account the money could have landed in, including the one on an old invoice template.: Instead: Check first. A reminder sent to a customer who paid you two days ago costs more goodwill than the day of delay costs you cash, and they will remember it for longer.
On a Monday morning about an invoice that was due on Saturday or Sunday.: Instead: Give it until Tuesday. Weekend due dates land in the next working day's run everywhere, and chasing on the Monday reveals that you are counting calendar days rather than working ones.
When the customer told you which payment run it would be in and that run has not happened yet.: Instead: Wait for the date they gave you, then use the missed-promise email if it passes. Chasing inside a window you agreed to is how you become the supplier whose emails get filtered.

Notes on this one

The line that does the work here is the one that says no reply is needed. It removes the only cost of ignoring you that the customer can feel — having to write back — and leaves the email doing its real job, which is putting the invoice back on top of a pile.

Attaching the invoice again matters more than it sounds. A reminder with nothing attached forces someone to go and find the original, and an email that creates work is an email that gets postponed.

Questions this comes with

How soon after the due date should you send the first reminder?: The next working day, once you have checked that the money has not already arrived. Waiting a week to be polite does not make you more likely to be paid; it just moves the whole conversation a week later, and by then the invoice has left the top of the pile. Sending on day one, in a tone that assumes an oversight, costs you nothing with a good customer and buys you six days with a bad one.
Should the first reminder mention late fees?: No. A late fee threat on day one is a consequence attached to something that might be a holiday or an approval queue, and you have nothing to escalate to afterwards. If your terms carry interest, the place to state it is the two-week email, after a neutral reminder has been ignored. Stating it once, calmly, at that point carries far more weight than stating it immediately.

All 19 reminder templates

Collectly does this across every invoice, on its own

You just picked the email to send on one invoice. Collectly does the same thing continuously for every unpaid invoice you have — reads the replies, works out why each one is unpaid, estimates when it will land, and drafts the follow-up for you to approve.

With 15 rules it cannot talk its way around

A paid or written-off invoice is never chased again. Follow-ups are switched off permanently, not deferred.
A disputed invoice stops automated chasing entirely and goes to a person to resolve.
A promise to pay on a date pauses reminders until that date has passed. Collectly checks back the day after, not on the day.
At least three days between reminders on the same invoice, so re-running the analysis cannot turn into nagging. A resent or corrected invoice the customer has just asked for is not a reminder, and still waits for your approval.

Try it on your invoices See how it works

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