Late fees on invoices in the US: what can you charge?

Potentially, yes.

Businesses commonly include late-payment provisions in their contracts and payment terms.

But the important word is include.

Trying to introduce a new late fee after a customer has already failed to pay is very different from enforcing a term both parties agreed before the work started.

A typical agreement might say that invoices are due within 30 days and that overdue amounts may incur a stated late charge.

The exact wording that works for your business depends on your state, contract and circumstances.

There is no single US-wide answer for ordinary B2B invoices.

This is one of the most important things to understand.

State law can differ, and specific rules can also apply to particular types of transactions.

So if you are looking for a sentence such as:

The maximum late fee in America is 5%.

There isn't one.

That is the safest place to deal with them.

Agree the terms before you provide the service.

Your contract or terms should make clear:

• When invoices are due.
• When an invoice becomes late.
• Whether there is a grace period.
• What late fee or interest may apply.
• Whether the charge is fixed or percentage-based.
• How often a recurring fee can be applied.
• Which state's law governs the agreement.

The customer should not be surprised by the charge after the invoice becomes overdue.

The right wording depends on the rules that apply to your business, so have important terms reviewed appropriately.

But structurally, a late-payment clause might look like this:

Payment is due within [Number] days of the invoice date.

Any undisputed amount not paid by the due date may be subject to a late fee of [Fee], to the extent permitted by applicable law.

Late fees will begin to apply [Number] days after the payment due date.

That is clearer than simply putting:

Late fees apply.

The customer should be able to work out what happens and when.

If your agreement uses a percentage and you have confirmed that it is permitted, the clause could be structured like this:

Invoices are due within [Number] days.

Overdue undisputed balances may incur a late fee of [Percentage]% per [Month/Period], or the maximum amount permitted by applicable law if lower.

The late fee will begin [Number] days after the invoice due date.

Do not copy a percentage from somebody else's contract without checking whether it works in your jurisdiction.

The wording is the easy part.

The legal entitlement is what matters.

Some businesses prefer a fixed amount.

The structure might look like:

Payment is due by the date shown on the invoice.

If an undisputed invoice remains unpaid for more than [Number] days after the due date, a late fee of [Amount] may be charged where permitted by applicable law.

Again, check that the fee itself is permitted and reasonable for the transaction.

Do not rely on tiny text added to the bottom of an invoice after the commercial agreement has already been made.

Where appropriate, payment terms can appear in:

• Your service agreement.
• Master services agreement.
• Proposal or statement of work.
• Terms and conditions.
• Customer onboarding documents.
• The invoice itself.

The contract is what establishes the agreement.

The invoice can then remind the customer of those terms.

You can choose to, subject to the terms and laws that apply.

For example:

Invoice due: October 1
Grace period: 5 days
Late charge applies: October 7

A grace period can be useful if occasional short payment delays are common and you do not want to add fees immediately.

Whether that makes sense commercially is up to you.

That depends on how your agreed term is structured.

Fixed fee

If the agreement allows a fixed $50 charge once the invoice becomes late:

$5,000 invoice + $50 fee = $5,050 due

Straightforward.

Percentage fee

Suppose the agreed and legally permitted fee is 1% for the relevant period.

On a $5,000 balance:

$5,000 × 1% = $50

The outstanding amount becomes:

$5,050

But be careful with recurring percentage charges.

The way a charge accumulates over multiple periods can significantly increase the effective rate.

That is another reason to get the clause right before using it.

QuickBooks Online currently supports automatic late fees on overdue invoices.

Businesses can configure:

• A fixed amount.
• A percentage.
• A combination of the two.
• How frequently the charge applies.
• A grace period.

QuickBooks also warns users to confirm what their jurisdiction permits before using the feature.

So the fact that your accounting software technically lets you enter a number does not mean that number is legally appropriate for your business.

Software settings are not legal advice.

Being entitled to charge one and choosing to charge one are different decisions.

Suppose a good customer has paid every invoice on time for three years.

One invoice is four days late.

You could immediately reach for the contract.

Or you could send:

Hi [Customer name],

I'm following up on invoice [Invoice number] for [Amount], which was due on [Due date].

Could you confirm when payment is scheduled?

If there's anything holding it up, let me know and I'll help get it resolved.

Thanks,

[Your name]

That may be the better commercial decision.

Now compare that with a customer who:

• Is 60 days overdue.
• Has ignored multiple emails.
• Has missed two payment promises.
• Has no dispute with the invoice.

The late-payment clause becomes much more relevant.

If the fee was agreed in advance, applies to the debt and you have checked the applicable rules, keep the email factual.

Hi [Customer name],

Invoice [Invoice number] for [Invoice amount] was due on [Due date] and remains unpaid.

Under our agreed payment terms, a late fee of [Late fee] has now been applied.

The current outstanding balance is [Total amount].

Please arrange payment by [Date], or let me know if there is an issue preventing payment.

Thanks,

[Your name]

Do not turn the email into a legal threat.

State what has happened and what you need next.

This changes things.

If the customer says:

This invoice is incorrect.

your first priority should be understanding what they believe is wrong.

Ask:

• Which part is disputed?
• What amount is disputed?
• Why?
• Who in your company needs to investigate it?

Pause normal chasing while a genuine dispute is being resolved.

Do not keep automatically adding fees while your own team is still trying to establish whether the invoice was correct.

For significant disputes, get appropriate legal advice.

Be very careful about adding it.

A sentence added to a new reminder after an invoice becomes overdue does not automatically change the agreement you already had with the customer.

Rather than improvising a penalty, review:

• Your signed contract.
• Proposal.
• Terms and conditions.
• Purchase order.
• Invoice terms.
• Applicable state law.

If the amount matters, ask a lawyer who works in the relevant state.

For future customers, fix the terms before the next contract is signed.

People often use these terms interchangeably, but they can be structured differently.

A late fee might be:

$50 once the account becomes overdue.

Interest might be:

X% applied to the unpaid balance over a specified period.

The legal treatment can also differ depending on the jurisdiction and transaction.

Do not assume that calling something a "fee" means rules governing interest or penalties cannot apply.

Get the structure reviewed if you plan to use it routinely.

A late fee is a term.

Collections is a process.

You can have perfect late-payment wording and still spend hours chasing the invoice.

The customer might say:

We need a PO.

It went to the wrong department.

We'll pay Friday.

We dispute the amount.

We already paid this.

A late fee does not resolve any of those.

Someone still needs to understand the reply and decide what happens next.

That is why effective accounts receivable combines good payment terms with a good collections process.

The better outcome is still getting paid on time.

A few things help.

Make the due date obvious

Write:

Payment due October 15

rather than relying only on:

Net 30

Send the invoice to the right person

Find out who actually processes it.

Get PO requirements sorted early

Ideally before the work starts.

Follow up before invoices become seriously overdue

A friendly reminder can uncover problems before they turn into 60-day debts.

Ask why an invoice is unpaid

Do not assume every delay is unwillingness to pay.

Track payment promises

"We'll pay Friday" should become an actual task for Friday.

Act when promises are missed

Do not wait another 30 days before checking again.

Our collections email sequence shows how to manage these different responses.