Landlord math toolkit

Late Fee Calculator

Estimate a late fee and the total amount due.

How We Calculated This

If the fee is flat, use the flat amount entered.
If the fee is percentage-based, multiply rent by the percent entered.
If both apply, add the flat fee and percentage amount to get the total late fee, then add it to unpaid rent.

Monthly rent is $1,950 with a $50 flat fee plus 3% of rent after a 5-day grace period.

This tool does not verify whether a late-fee structure is allowed in your jurisdiction.
Grace days are shown as context only and do not automatically delay the fee in the math.
Always check lease language and local law before charging a late fee.

This tool is for informational use only and is not legal, tax, or financial advice.

Does the calculator decide whether the fee is legal?

No. It only shows the math. Legal caps, grace periods, and notice rules vary by lease and location.

Can I use both a flat fee and a percent?

Yes, if that reflects your lease terms. Choose the combined option to include both pieces in the estimate.

Why is the grace period not changing the total?

Grace days are included as a note for the summary. The calculator assumes you are checking the amount once a fee is chargeable.