Late-fee & reminder rules freelancers should know (before you invoice a penalty)

A late fee is a contract term, not a surprise

The single most important rule: a late fee is only enforceable if the client agreed to it before the work was done and the invoice sent. That usually means it appears in your contract, proposal, or invoice terms that the client accepted. Springing a fee on an unpaid invoice the client never saw is both unfair and hard to collect.

This is not legal advice — rules vary by jurisdiction and by the contract you actually signed. The point is process: agree terms up front, then remind consistently.

What a fair late-fee setup looks like

The fee (or interest rate) is written in the agreement the client accepted.
The due date is explicit on every invoice.
The reminder cadence runs before any fee is applied — friendly, then firm, then final.
The final notice references the agreed fee rather than inventing one.

A late fee is a nudge backed by a contract, not a punishment delivered in anger.

Where reminders fit the process

Reminders are the humane front end of the same process. Most clients pay after a clear, friendly nudge — long before a fee matters. The fee exists as a backstop; the cadence does the day-to-day work of getting you paid.

Friendly at 0–14 days: surface the invoice.
Firm at 15–30 days: name a deadline.
Final before the fee: reference the agreed term.

What to avoid

Silent fees — a percentage buried in fine print the client never saw.
Retroactive fees — inventing a penalty after the invoice is late.
Threatening fees you cannot enforce — it undermines trust and rarely collects.

Authoritative references

U.S. Small Business Administration (contracts & collections): https://www.sba.gov/
Freelancers Union: https://www.freelancersunion.org/
SCORE: https://www.score.org/

FAQ

Can I add a late fee after the invoice is already late?

Generally no — a fee is only enforceable if the client agreed to it beforehand, usually in a signed contract or accepted terms. Dunner is not legal advice; confirm with a qualified professional in your jurisdiction.

Do I have to remind before charging a fee?

There is no universal rule, but a clear reminder cadence (friendly → firm → final) is both fairer and more effective. The final notice should reference the agreed fee rather than surprise the client with one.

What interest rate is "allowed"?

It depends on your jurisdiction and contract — some places cap rates or require specific language. This is not legal advice; check the rules that apply to your client's location and your agreement.

Should the reminder mention the fee?

Mention it in the final notice, referencing the term the client already accepted. Mentioning it in the friendly nudge usually reads as hostile and hurts the relationship.

Does Dunner calculate or charge late fees?

No. Dunner drafts reminder emails in the tone you choose. It does not calculate fees, charge them, or give legal advice — you apply your agreed terms.

## Disclaimer

Disclaimer (not legal advice): This article is general education about late-fee process, not legal advice. Late-fee enforceability, permitted rates, and collection rules vary by jurisdiction and by the contract you actually signed. Confirm terms with a qualified professional before invoicing penalties or escalating.

Try Dunner to keep your reminder cadence consistent so late fees stay a backstop, not a fight — try Dunner.