Late Fee on a $7,500 Invoice, 30 Days Overdue
Interest at 1.5% a month
$112.50
1.5% a month, simple interest charged pro rata by day, with no flat fee added.
How that number is worked out
These are the figures this page was built with and every line the calculator produces from them. Change anything above and all of it moves.
- Unpaid invoice amount7500 $
- Late fee rate you wrote in the contract1.5 % per month
- Days past due30
- Flat fee, if your contract has one0 $
Now owed$7,612.50
| Original invoice | $7,500.00 |
|---|---|
| Days late | 30 (1 months) |
| Interest at 1.5% a month | $112.50 |
| Flat fee | $0.00 |
| Total now due | $7,612.50 |
| Annual rate this equals | 18% |
| Per day from here | $3.75 |
Days past due compared
Interest is simple and pro rata by day, so it climbs in a straight line rather than accelerating.
| Days past due | Now owed | Total now due |
|---|---|---|
| 30 days | $7,612.50 | $7,612.50 |
| 60 days | $7,725.00 | $7,725.00 |
| 90 days | $7,837.50 | $7,837.50 |
| 120 days | $7,950.00 | $7,950.00 |
What else matters here
Seven thousand five hundred dollars 30 days late carries $112.50, a total of $7,612.50, and $3.75 a day. At 60 days the interest is $225.
Accrued interest is also something you can spend. Offering to waive the $112.50 in exchange for payment in full this week is a real concession the customer can take to whoever holds the money, and it costs you nothing you had before the invoice went late. It converts an argument about principle into a small, time limited deal.
Two rules make that work. Put the offer in writing with a date it expires, so it is an offer rather than a hint that the fee is negotiable in general. And only waive interest that has already accrued, never the clause itself, because a customer who learns the fee always disappears when they ask will ask every time.
What this calculator assumes
- A late fee is only collectable if it was in the contract or on the invoice before the invoice went late. A fee that first appears in a reminder email is not enforceable anywhere.
- 1.5 percent a month is 18 percent a year and is the common trade figure, but states cap this. Several cap it below 18 for consumer work, and a rate over the cap can void the whole fee clause, not just the excess.
- Interest here is simple, charged pro rata by day. Compounding monthly is legal in some states and not others, so the simple figure is the safe one to put on paper.
Questions people ask
What is the late fee on a $7,500 invoice at 30 days?
$112.50 at 1.5 percent a month, for a total of $7,612.50 and $3.75 a day after that.
Should I ever waive a late fee?
As a trade, yes. Waiving accrued interest in exchange for payment in full this week costs nothing you had before and gives the customer a reason to move.
How do I waive a fee without losing the clause?
Put it in writing, give it an expiry date, and waive only the interest already accrued on this invoice. Never suggest the clause itself is negotiable.
The late fee calculator takes any dimensions you like and hands back the same list.