The bill modifies the working families' tax credit in Washington State by clarifying its refundable nature, application requirements, and eligibility verification process. It reenacts and amends RCW 82.08.0206, establishing that the credit is funded by sales and use tax imposed on eligible low-income individuals starting from calendar years beginning on or after January 1, 2022. The bill specifies that eligible individuals must be Washington residents, have filed a federal income tax return, and have paid retail sales or use tax. It introduces a rebuttable presumption that individuals who were Washington residents during the year for which the credit is claimed have paid the necessary taxes.

Additionally, the bill outlines the refund amounts based on the number of qualifying children, with provisions for adjustments based on income levels and inflation. It mandates that the application process be accessible, including electronic and paper options, and requires individuals to maintain records for eligibility verification. The department is tasked with protecting personal data, conducting public information campaigns, and working with the IRS to automate credit administration. The act applies both prospectively and retroactively to January 1, 2023, ensuring that eligible individuals can claim refunds for prior years.