Late-Fee & Grace-Period Calculator

Type the rules from your lease to see the first day a late fee could apply and the amount (flat or percent, with optional cap). Not legal advice.

Not legal, tax, or financial advice. Landlord-tenant, late-fee, deposit and tax rules vary by state and locality - verify with local/state law or a qualified professional. Calculators run in your browser; nothing is sent or saved.

Monthly rent ($)Rent due dateGrace period (days)As-of date (today or a date to test)Date rent was fully paid (optional)

Late-fee type (from YOUR lease)Flat fee ($)Percent fee (% of rent)Fee cap ($, 0 = none)

Tracking rent for several units? The Rent Roll & Late-Fee Tracker spreadsheet applies your grace period and fee rule to every unit each month.

See it on Gumroad

Free download: Landlord Quick-Check

A free Excel (.xlsx) workbook: monthly rental cash flow and break-even rent, plus a late-fee and grace-period date calculator. Fictional sample data included; created with AI assistance and formula-tested.

Get the free Quick-Check

Delivered through our Gumroad store, which asks for an email address at checkout, even for free items.