Security deposit interest in Washington
Verified against RCW 59.18.270 and agency sources on 2026-07-04. Not legal advice.
Washington does not require landlords to pay interest on security deposits.
- Statute: RCW 59.18.270 · primary source
Deposits must be held in a trust account, and unless otherwise agreed in writing, interest on the account belongs to the LANDLORD (RCW 59.18.270). Seattle does NOT require interest; Seattle instead requires trust-account placement, disclosure, deposit caps, and installment rights (SMC 7.24).
Security deposit interest calculator
Frequently asked questions
Do landlords have to pay interest on security deposits in Washington?
No — Washington law (RCW 59.18.270) does not require deposit interest.
Anything else Washington landlords should know about deposit interest?
Deposits must be held in a trust account, and unless otherwise agreed in writing, interest on the account belongs to the LANDLORD (RCW 59.18.270). Seattle does NOT require interest; Seattle instead requires trust-account placement, disclosure, deposit caps, and installment rights (SMC 7.24).
Deposit interest in other states
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