Washington State Late Fee Calculator

Day 6 first day a late fee may apply
Rent limit
Not a fixed amount (see the statute box); manufactured/mobile home lot leases have a separate rule (below)
Earliest fee day
Day 6 after the due date
Statute
RCW 59.18.170(2)
Checked
What was not paid on time. Copies the rent until you type here.
How the lease sets the late fee
Washington lets a fee start on day 6, so this box starts at 5 days; typing less will not move that day.

Your late fee

$62.50

Check the statute

Paid 12 days late, after the 5-day grace period.

The Washington rule is not a simple cap: only its earliest fee day is applied here, so compare your fee with the statute text below.

Days past due
12 days
Grace period ends
October 24, 2026
Earliest fee date
October 25, 2026
Lease late fee
5% of $1,250.00 = $62.50
Rent + late fee
$1,312.50

Washington, earliest legal fee date: October 25, 2026

Late rent notice builder

Who it is from and to
Amounts
Taken from the calculator. Set 0 if the rent itself is paid.
Taken from the result; you may change it.
Adds the two above until you type your own figure.
Blank: the letter asks for payment at the earliest opportunity.
Payment and contact
Where and how the tenant can pay.
Late rent notice

[Your name or company]

Date: October 31, 2026

To: [Tenant name]

[Rental property address]

Re: Overdue rent for [Rental property address]

Dear [Tenant name],

This letter is a reminder that the rent of $1,250.00 for [Rental property address] was due on October 19, 2026. As of October 31, 2026, $1,250.00 of it is still unpaid (12 days past due).

Your lease provides for a late charge, which comes to $62.50.

Amount now due

Unpaid rent
$1,250.00
Late charge
$62.50
Total
$1,312.50

Please pay $1,312.50 at your earliest opportunity.

If this letter crossed with your payment, please disregard it.

Regards,

[Your name or company]

12% legal default rate (contract silent)
Max written B2B rate
Floating cap: higher of 12% or 26-week T-bill average +4 pts — business transactions are exempt (any agreed rate).
Cap regime
No statutory cap
Statute
RCW 19.52.010, 19.52.020
Verified
— how we verify · changelog

Legal rate where no different rate is agreed in writing; applied as prejudgment interest on liquidated claims.

Pre-filled with Washington's statutory default (12%), which governs only when the contract names no rate; a rate stated in your contract replaces it.

Interest at 12% a year

Interest owed on an overdue invoice in Washington at 12% per year
Invoice amount30 days late60 days late90 days late
$1,000.00$9.86$19.73$29.59
$5,000.00$49.32$98.63$147.95
$10,000.00$98.63$197.26$295.89

Maximum late fee in Washington State — written B2B contracts

No statutory cap

Basis: RCW 19.52.080.

About this page

Washington State rent late fee law

Washington State, RCW 59.18.170(2): rent paid no later than five days after it is due cannot carry a late fee. If it is paid later than that, the landlord may count late fees from the day after the due date up to the day of payment.

(2) The landlord may not charge a late fee for rent that is paid within five days following its due date. If rent is more than five days past due, the landlord may charge late fees commencing from the first day after the due date until paid.
— Wash. Rev. Code § 59.18.170(2). Read it at the official source · checked .

Manufactured/mobile home lots in Washington State

This applies to manufactured/mobile home lot agreements made or renewed from May 7, 2025 on: under such an agreement, rent that arrives no later than five days after the due date cannot be charged a late fee, and the monthly late fees are limited to 2% of the total rent in the first month the rent is past due, 3% in the second month in a row and 5% in the third and following months; when rent is more than five days late they may count from the day after the due date.

(2) Any rental agreement executed between the landlord and tenant shall not contain any provision: [...] (j) Allowing the landlord to charge a late fee for rent that is paid within five days following its due date for leases or rental agreements entered into or renewed on or after May 7, 2025. If rent is more than five days past due, the landlord may charge late fees commencing from the first day after the due date until paid. During the first month that rent is past due, late fees may not exceed two percent of the tenant's total rent per month. During the second consecutive month that rent is past due, late fees may not exceed three percent of the tenant's total rent per month. During the third consecutive month and all subsequent consecutive months that rent is past due, late fees may not exceed five percent of the tenant's total rent per month.
— Wash. Rev. Code § 59.20.060(2)(j). Read it at the official source · checked .

Before you send the late rent notice: it is a reminder letter about overdue rent and a late charge, not an eviction notice. A notice to pay rent or quit is a separate document, and Washington has its own rules for it. Nothing on this page is legal advice.

What Washington law says about invoice interest

(1) Except as provided in subsection (2) of this section, every loan or forbearance of money, goods, or thing in action shall bear interest at the rate of twelve percent per annum where no different rate is agreed to in writing between the parties [...]
— RCW 19.52.010(1). Read it at the official source · row verified 2026-08-19.

Business entities can't plead usury, and no one may plead it for a commercial/business/investment/agricultural-purpose deal — so B2B may exceed the 12% floating cap freely.

Profit and nonprofit corporations, Massachusetts trusts, associations, trusts, general partnerships, joint ventures, limited partnerships, and governments and governmental subdivisions, agencies, or instrumentalities may not plead the defense of usury nor maintain any action thereon or therefor, and persons may not plead the defense of usury nor maintain any action thereon or therefor if the transaction was primarily for agricultural, commercial, investment, or business purposes: PROVIDED, HOWEVER, That this section shall not apply to a consumer transaction of any amount.
— RCW 19.52.080. Read it at the official source · verified .

Not legal advice. Figures were last verified on the date shown; check the cited statute before charging a late fee.