RCW 51.16.190: Limitation on collection actions.

(1) "Action" means, but is not limited to, a notice of assessment pursuant to RCW 51.48.120, an action at law pursuant to RCW 51.16.150, or any other administrative or civil process authorized by this title for the determination of liability for premiums, assessments, penalties, contributions, or other sums, or the collection of premiums, assessments, penalties, contributions, or other sums.

(2) Any action to collect any delinquent premium, assessment, contribution, penalty, or other sum due to the department from any employer subject to this title shall be brought within three years of the date any such sum became due.

(3) In case of a false or fraudulent report with intent to evade premiums, assessments, contributions, penalties, interest, or other sums, or in the event of a failure to file a report, action may be begun at any time.

(4) Any claim for refund or adjustment by an employer of any premium, assessment, contribution, penalty, or other sum collected by the department shall be made in writing to the department within three years of the date the sum became due.